diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index b571530c5d9d7..180cd2ae2e160 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -262,9 +262,9 @@ namespace ts {
                     if (isStringOrNumericLiteral(nameExpression)) {
                         return escapeLeadingUnderscores(nameExpression.text);
                     }
-
-                    Debug.assert(isWellKnownSymbolSyntactically(nameExpression));
-                    return getPropertyNameForKnownSymbolName(idText((<PropertyAccessExpression>nameExpression).name));
+                    else {
+                        Debug.fail("Only computed properties with literal names have declaration names");
+                    }
                 }
                 return isPropertyNameLiteral(name) ? getEscapedTextOfIdentifierOrLiteral(name) : undefined;
             }
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 0eaffe07c02c9..bb374b4c912d6 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -452,6 +452,7 @@ namespace ts {
         // This allows users to just specify library files they want to used through --lib
         // and they will not get an error from not having unrelated library files
         let deferredGlobalESSymbolConstructorSymbol: Symbol | undefined;
+        let deferredGlobalESSymbolConstructorTypeSymbol: Symbol | undefined;
         let deferredGlobalESSymbolType: ObjectType;
         let deferredGlobalTypedPropertyDescriptorType: GenericType;
         let deferredGlobalPromiseType: GenericType;
@@ -4420,8 +4421,7 @@ namespace ts {
                     // Use explicitly specified property name ({ p: xxx } form), or otherwise the implied name ({ p } form)
                     const name = declaration.propertyName || <Identifier>declaration.name;
                     const isLate = isLateBindableName(name);
-                    const isWellKnown = isComputedPropertyName(name) && isWellKnownSymbolSyntactically(name.expression);
-                    if (!isLate && !isWellKnown && isComputedNonLiteralName(name)) {
+                    if (!isLate && isComputedNonLiteralName(name)) {
                         const exprType = checkExpression((name as ComputedPropertyName).expression);
                         if (isTypeAssignableToKind(exprType, TypeFlags.ESSymbolLike)) {
                             if (noImplicitAny) {
@@ -4444,9 +4444,7 @@ namespace ts {
                     // Use type of the specified property, or otherwise, for a numeric name, the type of the numeric index signature,
                     // or otherwise the type of the string index signature.
                     const nameType = isLate ? checkComputedPropertyName(name as ComputedPropertyName) as LiteralType | UniqueESSymbolType : undefined;
-                    const text = isLate ? getLateBoundNameFromType(nameType!) :
-                        isWellKnown ? getPropertyNameForKnownSymbolName(idText(((name as ComputedPropertyName).expression as PropertyAccessExpression).name)) :
-                        getTextOfPropertyName(name);
+                    const text = isLate ? getLateBoundNameFromType(nameType!) : getTextOfPropertyName(name);
 
                     // Relax null check on ambient destructuring parameters, since the parameters have no implementation and are just documentation
                     if (strictNullChecks && declaration.flags & NodeFlags.Ambient && isParameterDeclaration(declaration)) {
@@ -4839,6 +4837,12 @@ namespace ts {
                 : getTypeFromArrayBindingPattern(pattern, includePatternInType, reportErrors);
         }
 
+        function isGlobalSymbolConstructor(node: Node) {
+            const symbol = getSymbolOfNode(node);
+            const globalSymbol = getGlobalESSymbolConstructorTypeSymbol(/*reportErrors*/ false);
+            return globalSymbol && symbol && symbol === globalSymbol;
+        }
+
         // Return the type associated with a variable, parameter, or property declaration. In the simple case this is the type
         // specified in a type annotation or inferred from an initializer. However, in the case of a destructuring declaration it
         // is a bit more involved. For example:
@@ -4854,6 +4858,10 @@ namespace ts {
 
         function widenTypeForVariableLikeDeclaration(type: Type | undefined, declaration: any, reportErrors?: boolean) {
             if (type) {
+                // TODO: Remove the following SymbolConstructor special case when back compat with pre-3.0 libs isn't required
+                if (type.flags & TypeFlags.ESSymbol && isGlobalSymbolConstructor(declaration.parent)) {
+                    type = getESSymbolLikeTypeForNode(declaration);
+                }
                 if (reportErrors) {
                     reportErrorsFromWidening(declaration, type);
                 }
@@ -8235,6 +8243,10 @@ namespace ts {
             return deferredGlobalESSymbolConstructorSymbol || (deferredGlobalESSymbolConstructorSymbol = getGlobalValueSymbol("Symbol" as __String, reportErrors));
         }
 
+        function getGlobalESSymbolConstructorTypeSymbol(reportErrors: boolean) {
+            return deferredGlobalESSymbolConstructorTypeSymbol || (deferredGlobalESSymbolConstructorTypeSymbol = getGlobalTypeSymbol("SymbolConstructor" as __String, reportErrors));
+        }
+
         function getGlobalESSymbolType(reportErrors: boolean) {
             return deferredGlobalESSymbolType || (deferredGlobalESSymbolType = getGlobalType("Symbol" as __String, /*arity*/ 0, reportErrors)) || emptyObjectType;
         }
@@ -8894,10 +8906,7 @@ namespace ts {
 
         function getPropertyTypeForIndexType(objectType: Type, indexType: Type, accessNode: ElementAccessExpression | IndexedAccessTypeNode | undefined, cacheSymbol: boolean) {
             const accessExpression = accessNode && accessNode.kind === SyntaxKind.ElementAccessExpression ? accessNode : undefined;
-            const propName = isTypeUsableAsLateBoundName(indexType) ? getLateBoundNameFromType(indexType) :
-                accessExpression && checkThatExpressionIsProperSymbolReference(accessExpression.argumentExpression, indexType, /*reportError*/ false) ?
-                    getPropertyNameForKnownSymbolName(idText((<PropertyAccessExpression>accessExpression.argumentExpression).name)) :
-                    undefined;
+            const propName = isTypeUsableAsLateBoundName(indexType) ? getLateBoundNameFromType(indexType) : undefined;
             if (propName !== undefined) {
                 const prop = getPropertyOfType(objectType, propName);
                 if (prop) {
@@ -16359,9 +16368,6 @@ namespace ts {
                     !isTypeAssignableTo(links.resolvedType, stringNumberSymbolType)) {
                     error(node, Diagnostics.A_computed_property_name_must_be_of_type_string_number_symbol_or_any);
                 }
-                else {
-                    checkThatExpressionIsProperSymbolReference(node.expression, links.resolvedType, /*reportError*/ true);
-                }
             }
 
             return links.resolvedType;
@@ -16403,7 +16409,7 @@ namespace ts {
             for (let i = 0; i < node.properties.length; i++) {
                 const memberDecl = node.properties[i];
                 let member = getSymbolOfNode(memberDecl);
-                const computedNameType = memberDecl.name && memberDecl.name.kind === SyntaxKind.ComputedPropertyName && !isWellKnownSymbolSyntactically(memberDecl.name.expression) ?
+                const computedNameType = memberDecl.name && memberDecl.name.kind === SyntaxKind.ComputedPropertyName ?
                     checkComputedPropertyName(memberDecl.name) : undefined;
                 if (memberDecl.kind === SyntaxKind.PropertyAssignment ||
                     memberDecl.kind === SyntaxKind.ShorthandPropertyAssignment ||
@@ -16493,7 +16499,10 @@ namespace ts {
                 }
 
                 if (computedNameType && !(computedNameType.flags & TypeFlags.StringOrNumberLiteralOrUnique)) {
-                    if (isTypeAssignableTo(computedNameType, stringNumberSymbolType)) {
+                    if (isTypeAny(computedNameType)) {
+                        hasComputedStringProperty = true; // string is the closest to a catch-all index signature we have
+                    }
+                    else if (isTypeAssignableTo(computedNameType, stringNumberSymbolType)) {
                         if (isTypeAssignableTo(computedNameType, numberType)) {
                             hasComputedNumberProperty = true;
                         }
@@ -16506,6 +16515,10 @@ namespace ts {
                     }
                 }
                 else {
+                    if (computedNameType && propertiesTable.get(member.escapedName) && !isGetOrSetAccessorDeclaration(memberDecl)) {
+                        // The binder issues error for normal duplicate props, but for computed names we must do so here
+                        error(memberDecl.name, Diagnostics.Duplicate_declaration_0, getNameOfSymbolAsWritten(member));
+                    }
                     propertiesTable.set(member.escapedName, member);
                 }
                 propertiesArray.push(member);
@@ -17980,48 +17993,6 @@ namespace ts {
             return checkIndexedAccessIndexType(getIndexedAccessType(objectType, indexType, node), node);
         }
 
-        function checkThatExpressionIsProperSymbolReference(expression: Expression, expressionType: Type, reportError: boolean): boolean {
-            if (expressionType === errorType) {
-                // There is already an error, so no need to report one.
-                return false;
-            }
-
-            if (!isWellKnownSymbolSyntactically(expression)) {
-                return false;
-            }
-
-            // Make sure the property type is the primitive symbol type
-            if ((expressionType.flags & TypeFlags.ESSymbolLike) === 0) {
-                if (reportError) {
-                    error(expression, Diagnostics.A_computed_property_name_of_the_form_0_must_be_of_type_symbol, getTextOfNode(expression));
-                }
-                return false;
-            }
-
-            // The name is Symbol.<someName>, so make sure Symbol actually resolves to the
-            // global Symbol object
-            const leftHandSide = <Identifier>(<PropertyAccessExpression>expression).expression;
-            const leftHandSideSymbol = getResolvedSymbol(leftHandSide);
-            if (!leftHandSideSymbol) {
-                return false;
-            }
-
-            const globalESSymbol = getGlobalESSymbolConstructorSymbol(/*reportErrors*/ true);
-            if (!globalESSymbol) {
-                // Already errored when we tried to look up the symbol
-                return false;
-            }
-
-            if (leftHandSideSymbol !== globalESSymbol) {
-                if (reportError) {
-                    error(leftHandSide, Diagnostics.Symbol_reference_does_not_refer_to_the_global_Symbol_constructor_object);
-                }
-                return false;
-            }
-
-            return true;
-        }
-
         function callLikeExpressionMayHaveTypeArguments(node: CallLikeExpression): node is CallExpression | NewExpression {
             // TODO: Also include tagged templates (https://github.com/Microsoft/TypeScript/issues/11947)
             return isCallOrNewExpression(node);
@@ -24320,6 +24291,12 @@ namespace ts {
             return arrayElementType;
         }
 
+        function getPropertyNameForKnownSymbolName(symbolName: string): __String {
+            const ctorType = getGlobalESSymbolConstructorSymbol(/*reportErrors*/ false);
+            const uniqueType = ctorType && getTypeOfPropertyOfType(getTypeOfSymbol(ctorType), escapeLeadingUnderscores(symbolName));
+            return uniqueType && isTypeUsableAsLateBoundName(uniqueType) ? getLateBoundNameFromType(uniqueType) : `__@${symbolName}` as __String;
+        }
+
         /**
          * We want to treat type as an iterable, and get the type it is an iterable of. The iterable
          * must have the following structure (annotated with the names of the variables below):
@@ -24542,7 +24519,7 @@ namespace ts {
 
         function isGetAccessorWithAnnotatedSetAccessor(node: SignatureDeclaration) {
             return node.kind === SyntaxKind.GetAccessor
-                && getEffectiveSetAccessorTypeAnnotationNode(getDeclarationOfKind<SetAccessorDeclaration>(node.symbol, SyntaxKind.SetAccessor)!) !== undefined;
+                && getEffectiveSetAccessorTypeAnnotationNode(getDeclarationOfKind<SetAccessorDeclaration>(getSymbolOfNode(node), SyntaxKind.SetAccessor)!) !== undefined;
         }
 
         function isUnwrappedReturnTypeVoidOrAny(func: SignatureDeclaration, returnType: Type): boolean {
diff --git a/src/compiler/transformers/ts.ts b/src/compiler/transformers/ts.ts
index 4a696c6d130bf..7340e4e8c6dc3 100644
--- a/src/compiler/transformers/ts.ts
+++ b/src/compiler/transformers/ts.ts
@@ -2108,8 +2108,7 @@ namespace ts {
          * any such locations
          */
         function isSimpleInlineableExpression(expression: Expression) {
-            return !isIdentifier(expression) && isSimpleCopiableExpression(expression) ||
-                isWellKnownSymbolSyntactically(expression);
+            return !isIdentifier(expression) && isSimpleCopiableExpression(expression);
         }
 
         /**
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 6064ef4e6a5f4..f9a1e5a3010aa 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -2566,17 +2566,7 @@ namespace ts {
 
     export function isDynamicName(name: DeclarationName): boolean {
         return name.kind === SyntaxKind.ComputedPropertyName &&
-            !isStringOrNumericLiteral(name.expression) &&
-            !isWellKnownSymbolSyntactically(name.expression);
-    }
-
-    /**
-     * Checks if the expression is of the form:
-     *    Symbol.name
-     * where Symbol is literally the word "Symbol", and name is any identifierName
-     */
-    export function isWellKnownSymbolSyntactically(node: Expression): boolean {
-        return isPropertyAccessExpression(node) && isESSymbolIdentifier(node.expression);
+            !isStringOrNumericLiteral(name.expression);
     }
 
     export function getPropertyNameForPropertyNameNode(name: DeclarationName): __String | undefined {
@@ -2588,10 +2578,7 @@ namespace ts {
         }
         if (name.kind === SyntaxKind.ComputedPropertyName) {
             const nameExpression = name.expression;
-            if (isWellKnownSymbolSyntactically(nameExpression)) {
-                return getPropertyNameForKnownSymbolName(idText((<PropertyAccessExpression>nameExpression).name));
-            }
-            else if (nameExpression.kind === SyntaxKind.StringLiteral || nameExpression.kind === SyntaxKind.NumericLiteral) {
+            if (nameExpression.kind === SyntaxKind.StringLiteral || nameExpression.kind === SyntaxKind.NumericLiteral) {
                 return escapeLeadingUnderscores((<LiteralExpression>nameExpression).text);
             }
         }
@@ -2619,10 +2606,6 @@ namespace ts {
         return node.kind === SyntaxKind.Identifier ? node.escapedText : escapeLeadingUnderscores(node.text);
     }
 
-    export function getPropertyNameForKnownSymbolName(symbolName: string): __String {
-        return "__@" + symbolName as __String;
-    }
-
     export function isKnownSymbol(symbol: Symbol): boolean {
         return startsWith(symbol.escapedName as string, "__@");
     }
diff --git a/src/harness/fourslash.ts b/src/harness/fourslash.ts
index 3465ef333a0a0..758764f217b9e 100644
--- a/src/harness/fourslash.ts
+++ b/src/harness/fourslash.ts
@@ -2300,9 +2300,7 @@ Actual: ${stringify(fullActual)}`);
 
         private verifyFileContent(fileName: string, text: string) {
             const actual = this.getFileContent(fileName);
-            if (actual !== text) {
-                throw new Error(`verifyFileContent failed:\n${showTextDiff(text, actual)}`);
-            }
+            assert.equal(actual, text, "verifyFileContent failed");
         }
 
         public verifyTextAtCaretIs(text: string) {
diff --git a/src/lib/es2015.iterable.d.ts b/src/lib/es2015.iterable.d.ts
index 568d3596ddae3..595fc80ad9325 100644
--- a/src/lib/es2015.iterable.d.ts
+++ b/src/lib/es2015.iterable.d.ts
@@ -5,7 +5,7 @@ interface SymbolConstructor {
      * A method that returns the default iterator for an object. Called by the semantics of the
      * for-of statement.
      */
-    readonly iterator: symbol;
+    readonly iterator: unique symbol;
 }
 
 interface IteratorResult<T> {
diff --git a/src/lib/es2015.symbol.wellknown.d.ts b/src/lib/es2015.symbol.wellknown.d.ts
index 948c8129a92e6..d086758ee2fab 100644
--- a/src/lib/es2015.symbol.wellknown.d.ts
+++ b/src/lib/es2015.symbol.wellknown.d.ts
@@ -5,61 +5,61 @@ interface SymbolConstructor {
      * A method that determines if a constructor object recognizes an object as one of the
      * constructor’s instances. Called by the semantics of the instanceof operator.
      */
-    readonly hasInstance: symbol;
+    readonly hasInstance: unique symbol;
 
     /**
      * A Boolean value that if true indicates that an object should flatten to its array elements
      * by Array.prototype.concat.
      */
-    readonly isConcatSpreadable: symbol;
+    readonly isConcatSpreadable: unique symbol;
 
     /**
      * A regular expression method that matches the regular expression against a string. Called
      * by the String.prototype.match method.
      */
-    readonly match: symbol;
+    readonly match: unique symbol;
 
     /**
      * A regular expression method that replaces matched substrings of a string. Called by the
      * String.prototype.replace method.
      */
-    readonly replace: symbol;
+    readonly replace: unique symbol;
 
     /**
      * A regular expression method that returns the index within a string that matches the
      * regular expression. Called by the String.prototype.search method.
      */
-    readonly search: symbol;
+    readonly search: unique symbol;
 
     /**
      * A function valued property that is the constructor function that is used to create
      * derived objects.
      */
-    readonly species: symbol;
+    readonly species: unique symbol;
 
     /**
      * A regular expression method that splits a string at the indices that match the regular
      * expression. Called by the String.prototype.split method.
      */
-    readonly split: symbol;
+    readonly split: unique symbol;
 
     /**
      * A method that converts an object to a corresponding primitive value.
      * Called by the ToPrimitive abstract operation.
      */
-    readonly toPrimitive: symbol;
+    readonly toPrimitive: unique symbol;
 
     /**
      * A String value that is used in the creation of the default string description of an object.
      * Called by the built-in method Object.prototype.toString.
      */
-    readonly toStringTag: symbol;
+    readonly toStringTag: unique symbol;
 
     /**
      * An Object whose own property names are property names that are excluded from the 'with'
      * environment bindings of the associated objects.
      */
-    readonly unscopables: symbol;
+    readonly unscopables: unique symbol;
 }
 
 interface Symbol {
diff --git a/src/lib/esnext.asynciterable.d.ts b/src/lib/esnext.asynciterable.d.ts
index 11093af623dee..3ef271102861f 100644
--- a/src/lib/esnext.asynciterable.d.ts
+++ b/src/lib/esnext.asynciterable.d.ts
@@ -6,7 +6,7 @@ interface SymbolConstructor {
      * A method that returns the default async iterator for an object. Called by the semantics of
      * the for-await-of statement.
      */
-    readonly asyncIterator: symbol;
+    readonly asyncIterator: unique symbol;
 }
 
 interface AsyncIterator<T> {
diff --git a/src/services/navigationBar.ts b/src/services/navigationBar.ts
index 2f928f52c7b62..6180fa2838fe6 100644
--- a/src/services/navigationBar.ts
+++ b/src/services/navigationBar.ts
@@ -171,16 +171,12 @@ namespace ts.NavigationBar {
             case SyntaxKind.GetAccessor:
             case SyntaxKind.SetAccessor:
             case SyntaxKind.MethodSignature:
-                if (!hasDynamicName((<ClassElement | TypeElement>node))) {
-                    addNodeWithRecursiveChild(node, (<FunctionLikeDeclaration>node).body);
-                }
+                addNodeWithRecursiveChild(node, (<FunctionLikeDeclaration>node).body);
                 break;
 
             case SyntaxKind.PropertyDeclaration:
             case SyntaxKind.PropertySignature:
-                if (!hasDynamicName((<ClassElement | TypeElement>node))) {
-                    addLeafNode(node);
-                }
+                addLeafNode(node);
                 break;
 
             case SyntaxKind.ImportClause:
@@ -410,7 +406,8 @@ namespace ts.NavigationBar {
 
         const declName = getNameOfDeclaration(<Declaration>node);
         if (declName) {
-            return unescapeLeadingUnderscores(getPropertyNameForPropertyNameNode(declName)!); // TODO: GH#18217
+            const candidate = getPropertyNameForPropertyNameNode(declName);
+            return candidate ? unescapeLeadingUnderscores(candidate) : getTextOfNode(declName);
         }
         switch (node.kind) {
             case SyntaxKind.FunctionExpression:
diff --git a/tests/baselines/reference/ES5For-ofTypeCheck10.errors.txt b/tests/baselines/reference/ES5For-ofTypeCheck10.errors.txt
index 232f476f66c62..d5575857f026d 100644
--- a/tests/baselines/reference/ES5For-ofTypeCheck10.errors.txt
+++ b/tests/baselines/reference/ES5For-ofTypeCheck10.errors.txt
@@ -1,8 +1,7 @@
-tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts(9,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts(14,15): error TS2569: Type 'StringIterator' is not an array type or a string type. Use compiler option '--downlevelIteration' to allow iterating of iterators.
 
 
-==== tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts (2 errors) ====
+==== tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts (1 errors) ====
     // In ES3/5, you cannot for...of over an arbitrary iterable.
     class StringIterator {
         next() {
@@ -12,8 +11,6 @@ tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts(14,1
             };
         }
         [Symbol.iterator]() {
-         ~~~~~~
-!!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
             return this;
         }
     }
diff --git a/tests/baselines/reference/ES5For-ofTypeCheck10.symbols b/tests/baselines/reference/ES5For-ofTypeCheck10.symbols
index 5267dd2fbc5e1..103ded7637119 100644
--- a/tests/baselines/reference/ES5For-ofTypeCheck10.symbols
+++ b/tests/baselines/reference/ES5For-ofTypeCheck10.symbols
@@ -17,6 +17,9 @@ class StringIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : Symbol(StringIterator[Symbol.iterator], Decl(ES5For-ofTypeCheck10.ts, 7, 5))
+>Symbol.iterator : Symbol(SymbolConstructor.iterator, Decl(lib.es2015.iterable.d.ts, --, --))
+>Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(lib.es2015.symbol.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))
+>iterator : Symbol(SymbolConstructor.iterator, Decl(lib.es2015.iterable.d.ts, --, --))
 
         return this;
 >this : Symbol(StringIterator, Decl(ES5For-ofTypeCheck10.ts, 0, 0))
diff --git a/tests/baselines/reference/ES5For-ofTypeCheck10.types b/tests/baselines/reference/ES5For-ofTypeCheck10.types
index a8f8d99050651..2503c1e1da309 100644
--- a/tests/baselines/reference/ES5For-ofTypeCheck10.types
+++ b/tests/baselines/reference/ES5For-ofTypeCheck10.types
@@ -21,9 +21,9 @@ class StringIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : any
->Symbol : any
->iterator : any
+>Symbol.iterator : unique symbol
+>Symbol : SymbolConstructor
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/ES5SymbolProperty1.errors.txt b/tests/baselines/reference/ES5SymbolProperty1.errors.txt
deleted file mode 100644
index 1b135dcc91670..0000000000000
--- a/tests/baselines/reference/ES5SymbolProperty1.errors.txt
+++ /dev/null
@@ -1,16 +0,0 @@
-tests/cases/conformance/Symbols/ES5SymbolProperty1.ts(7,6): error TS2471: A computed property name of the form 'Symbol.foo' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/Symbols/ES5SymbolProperty1.ts (1 errors) ====
-    interface SymbolConstructor {
-        foo: string;
-    }
-    var Symbol: SymbolConstructor;
-    
-    var obj = {
-        [Symbol.foo]: 0
-         ~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.foo' must be of type 'symbol'.
-    }
-    
-    obj[Symbol.foo];
\ No newline at end of file
diff --git a/tests/baselines/reference/ES5SymbolProperty1.types b/tests/baselines/reference/ES5SymbolProperty1.types
index 7d76614f798cf..2a98d892b2d37 100644
--- a/tests/baselines/reference/ES5SymbolProperty1.types
+++ b/tests/baselines/reference/ES5SymbolProperty1.types
@@ -10,8 +10,8 @@ var Symbol: SymbolConstructor;
 >SymbolConstructor : SymbolConstructor
 
 var obj = {
->obj : { [Symbol.foo]: number; }
->{    [Symbol.foo]: 0} : { [Symbol.foo]: number; }
+>obj : { [x: string]: number; }
+>{    [Symbol.foo]: 0} : { [x: string]: number; }
 
     [Symbol.foo]: 0
 >[Symbol.foo] : number
@@ -22,8 +22,8 @@ var obj = {
 }
 
 obj[Symbol.foo];
->obj[Symbol.foo] : any
->obj : { [Symbol.foo]: number; }
+>obj[Symbol.foo] : number
+>obj : { [x: string]: number; }
 >Symbol.foo : string
 >Symbol : SymbolConstructor
 >foo : string
diff --git a/tests/baselines/reference/ES5SymbolProperty2.errors.txt b/tests/baselines/reference/ES5SymbolProperty2.errors.txt
index 0535da56f0616..ddb25232edf1a 100644
--- a/tests/baselines/reference/ES5SymbolProperty2.errors.txt
+++ b/tests/baselines/reference/ES5SymbolProperty2.errors.txt
@@ -1,15 +1,12 @@
-tests/cases/conformance/Symbols/ES5SymbolProperty2.ts(5,10): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
 tests/cases/conformance/Symbols/ES5SymbolProperty2.ts(10,11): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/Symbols/ES5SymbolProperty2.ts (2 errors) ====
+==== tests/cases/conformance/Symbols/ES5SymbolProperty2.ts (1 errors) ====
     module M {
         var Symbol: any;
     
         export class C {
             [Symbol.iterator]() { }
-             ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
         }
         (new C)[Symbol.iterator];
     }
diff --git a/tests/baselines/reference/ES5SymbolProperty3.errors.txt b/tests/baselines/reference/ES5SymbolProperty3.errors.txt
deleted file mode 100644
index 2953ed6ac6ab1..0000000000000
--- a/tests/baselines/reference/ES5SymbolProperty3.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/Symbols/ES5SymbolProperty3.ts(4,6): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/Symbols/ES5SymbolProperty3.ts (1 errors) ====
-    var Symbol: any;
-    
-    class C {
-        [Symbol.iterator]() { }
-         ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-    }
-    
-    (new C)[Symbol.iterator]
\ No newline at end of file
diff --git a/tests/baselines/reference/ES5SymbolProperty4.errors.txt b/tests/baselines/reference/ES5SymbolProperty4.errors.txt
deleted file mode 100644
index 18f065c6bd5fc..0000000000000
--- a/tests/baselines/reference/ES5SymbolProperty4.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/Symbols/ES5SymbolProperty4.ts(4,6): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/Symbols/ES5SymbolProperty4.ts (1 errors) ====
-    var Symbol: { iterator: string };
-    
-    class C {
-        [Symbol.iterator]() { }
-         ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-    }
-    
-    (new C)[Symbol.iterator]
\ No newline at end of file
diff --git a/tests/baselines/reference/ES5SymbolProperty5.errors.txt b/tests/baselines/reference/ES5SymbolProperty5.errors.txt
index fb3a9aa78d48e..2a7ac51a63b25 100644
--- a/tests/baselines/reference/ES5SymbolProperty5.errors.txt
+++ b/tests/baselines/reference/ES5SymbolProperty5.errors.txt
@@ -2,7 +2,7 @@ tests/cases/conformance/Symbols/ES5SymbolProperty5.ts(7,1): error TS2554: Expect
 
 
 ==== tests/cases/conformance/Symbols/ES5SymbolProperty5.ts (1 errors) ====
-    var Symbol: { iterator: symbol };
+    var Symbol: { readonly iterator: unique symbol };
     
     class C {
         [Symbol.iterator]() { }
diff --git a/tests/baselines/reference/ES5SymbolProperty5.js b/tests/baselines/reference/ES5SymbolProperty5.js
index c146b8dd5f1e5..c332ecf146583 100644
--- a/tests/baselines/reference/ES5SymbolProperty5.js
+++ b/tests/baselines/reference/ES5SymbolProperty5.js
@@ -1,5 +1,5 @@
 //// [ES5SymbolProperty5.ts]
-var Symbol: { iterator: symbol };
+var Symbol: { readonly iterator: unique symbol };
 
 class C {
     [Symbol.iterator]() { }
diff --git a/tests/baselines/reference/ES5SymbolProperty5.symbols b/tests/baselines/reference/ES5SymbolProperty5.symbols
index c5610b9ce2c4b..a954b0ca0320e 100644
--- a/tests/baselines/reference/ES5SymbolProperty5.symbols
+++ b/tests/baselines/reference/ES5SymbolProperty5.symbols
@@ -1,10 +1,10 @@
 === tests/cases/conformance/Symbols/ES5SymbolProperty5.ts ===
-var Symbol: { iterator: symbol };
+var Symbol: { readonly iterator: unique symbol };
 >Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(ES5SymbolProperty5.ts, 0, 3))
 >iterator : Symbol(iterator, Decl(ES5SymbolProperty5.ts, 0, 13))
 
 class C {
->C : Symbol(C, Decl(ES5SymbolProperty5.ts, 0, 33))
+>C : Symbol(C, Decl(ES5SymbolProperty5.ts, 0, 49))
 
     [Symbol.iterator]() { }
 >[Symbol.iterator] : Symbol(C[Symbol.iterator], Decl(ES5SymbolProperty5.ts, 2, 9))
@@ -14,7 +14,7 @@ class C {
 }
 
 (new C)[Symbol.iterator](0) // Should error
->C : Symbol(C, Decl(ES5SymbolProperty5.ts, 0, 33))
+>C : Symbol(C, Decl(ES5SymbolProperty5.ts, 0, 49))
 >Symbol.iterator : Symbol(iterator, Decl(ES5SymbolProperty5.ts, 0, 13))
 >Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(ES5SymbolProperty5.ts, 0, 3))
 >iterator : Symbol(iterator, Decl(ES5SymbolProperty5.ts, 0, 13))
diff --git a/tests/baselines/reference/ES5SymbolProperty5.types b/tests/baselines/reference/ES5SymbolProperty5.types
index 1b9ce23873744..6484aedddedef 100644
--- a/tests/baselines/reference/ES5SymbolProperty5.types
+++ b/tests/baselines/reference/ES5SymbolProperty5.types
@@ -1,16 +1,16 @@
 === tests/cases/conformance/Symbols/ES5SymbolProperty5.ts ===
-var Symbol: { iterator: symbol };
->Symbol : { iterator: symbol; }
->iterator : symbol
+var Symbol: { readonly iterator: unique symbol };
+>Symbol : { readonly iterator: unique symbol; }
+>iterator : unique symbol
 
 class C {
 >C : C
 
     [Symbol.iterator]() { }
 >[Symbol.iterator] : () => void
->Symbol.iterator : symbol
->Symbol : { iterator: symbol; }
->iterator : symbol
+>Symbol.iterator : unique symbol
+>Symbol : { readonly iterator: unique symbol; }
+>iterator : unique symbol
 }
 
 (new C)[Symbol.iterator](0) // Should error
@@ -19,8 +19,8 @@ class C {
 >(new C) : C
 >new C : C
 >C : typeof C
->Symbol.iterator : symbol
->Symbol : { iterator: symbol; }
->iterator : symbol
+>Symbol.iterator : unique symbol
+>Symbol : { readonly iterator: unique symbol; }
+>iterator : unique symbol
 >0 : 0
 
diff --git a/tests/baselines/reference/ES5SymbolProperty7.errors.txt b/tests/baselines/reference/ES5SymbolProperty7.errors.txt
deleted file mode 100644
index 21f6f005b3c0f..0000000000000
--- a/tests/baselines/reference/ES5SymbolProperty7.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/Symbols/ES5SymbolProperty7.ts(4,6): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/Symbols/ES5SymbolProperty7.ts (1 errors) ====
-    var Symbol: { iterator: any };
-    
-    class C {
-        [Symbol.iterator]() { }
-         ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-    }
-    
-    (new C)[Symbol.iterator]
\ No newline at end of file
diff --git a/tests/baselines/reference/FunctionDeclaration8_es6.types b/tests/baselines/reference/FunctionDeclaration8_es6.types
index 2588f042add9a..ebd9a509ae174 100644
--- a/tests/baselines/reference/FunctionDeclaration8_es6.types
+++ b/tests/baselines/reference/FunctionDeclaration8_es6.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/functionDeclarations/FunctionDeclaration8_es6.ts ===
 var v = { [yield]: foo }
->v : { [x: number]: any; }
->{ [yield]: foo } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ [yield]: foo } : { [x: string]: any; }
 >[yield] : any
 >yield : any
 >foo : any
diff --git a/tests/baselines/reference/FunctionDeclaration9_es6.types b/tests/baselines/reference/FunctionDeclaration9_es6.types
index 2b915b82a67b1..ddd1365303525 100644
--- a/tests/baselines/reference/FunctionDeclaration9_es6.types
+++ b/tests/baselines/reference/FunctionDeclaration9_es6.types
@@ -3,8 +3,8 @@ function * foo() {
 >foo : () => IterableIterator<any>
 
   var v = { [yield]: foo }
->v : { [x: number]: () => IterableIterator<any>; }
->{ [yield]: foo } : { [x: number]: () => IterableIterator<any>; }
+>v : { [x: string]: () => IterableIterator<any>; }
+>{ [yield]: foo } : { [x: string]: () => IterableIterator<any>; }
 >[yield] : () => IterableIterator<any>
 >yield : any
 >foo : () => IterableIterator<any>
diff --git a/tests/baselines/reference/FunctionPropertyAssignments5_es6.types b/tests/baselines/reference/FunctionPropertyAssignments5_es6.types
index 9430360e9da25..7c49b8e9906ba 100644
--- a/tests/baselines/reference/FunctionPropertyAssignments5_es6.types
+++ b/tests/baselines/reference/FunctionPropertyAssignments5_es6.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/functionPropertyAssignments/FunctionPropertyAssignments5_es6.ts ===
 var v = { *[foo()]() { } }
->v : { [x: number]: () => IterableIterator<any>; }
->{ *[foo()]() { } } : { [x: number]: () => IterableIterator<any>; }
+>v : { [x: string]: () => IterableIterator<any>; }
+>{ *[foo()]() { } } : { [x: string]: () => IterableIterator<any>; }
 >[foo()] : () => IterableIterator<any>
 >foo() : any
 >foo : any
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index 6c3499172187a..ee7349404a248 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -6375,18 +6375,11 @@ declare namespace ts {
      */
     function hasDynamicName(declaration: Declaration): declaration is DynamicNamedDeclaration;
     function isDynamicName(name: DeclarationName): boolean;
-    /**
-     * Checks if the expression is of the form:
-     *    Symbol.name
-     * where Symbol is literally the word "Symbol", and name is any identifierName
-     */
-    function isWellKnownSymbolSyntactically(node: Expression): boolean;
     function getPropertyNameForPropertyNameNode(name: DeclarationName): __String | undefined;
     type PropertyNameLiteral = Identifier | StringLiteralLike | NumericLiteral;
     function isPropertyNameLiteral(node: Node): node is PropertyNameLiteral;
     function getTextOfIdentifierOrLiteral(node: PropertyNameLiteral): string;
     function getEscapedTextOfIdentifierOrLiteral(node: PropertyNameLiteral): __String;
-    function getPropertyNameForKnownSymbolName(symbolName: string): __String;
     function isKnownSymbol(symbol: Symbol): boolean;
     /**
      * Includes the word "Symbol" with unicode escapes
diff --git a/tests/baselines/reference/argumentsObjectIterator02_ES6.types b/tests/baselines/reference/argumentsObjectIterator02_ES6.types
index a494a45f9356b..07aa33168f15a 100644
--- a/tests/baselines/reference/argumentsObjectIterator02_ES6.types
+++ b/tests/baselines/reference/argumentsObjectIterator02_ES6.types
@@ -9,9 +9,9 @@ function doubleAndReturnAsArray(x: number, y: number, z: number): [number, numbe
 >blah : () => IterableIterator<any>
 >arguments[Symbol.iterator] : () => IterableIterator<any>
 >arguments : IArguments
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
     let result = [];
 >result : any[]
diff --git a/tests/baselines/reference/asyncArrowFunction8_es2017.types b/tests/baselines/reference/asyncArrowFunction8_es2017.types
index 9e8ca263df443..3435d0fa63599 100644
--- a/tests/baselines/reference/asyncArrowFunction8_es2017.types
+++ b/tests/baselines/reference/asyncArrowFunction8_es2017.types
@@ -5,8 +5,8 @@ var foo = async (): Promise<void> => {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/asyncArrowFunction8_es5.types b/tests/baselines/reference/asyncArrowFunction8_es5.types
index 8fd401139959c..7c754a99de89b 100644
--- a/tests/baselines/reference/asyncArrowFunction8_es5.types
+++ b/tests/baselines/reference/asyncArrowFunction8_es5.types
@@ -5,8 +5,8 @@ var foo = async (): Promise<void> => {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/asyncArrowFunction8_es6.types b/tests/baselines/reference/asyncArrowFunction8_es6.types
index 7c53be7843ed2..9bd96c3fb3aa6 100644
--- a/tests/baselines/reference/asyncArrowFunction8_es6.types
+++ b/tests/baselines/reference/asyncArrowFunction8_es6.types
@@ -5,8 +5,8 @@ var foo = async (): Promise<void> => {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration8_es2017.types b/tests/baselines/reference/asyncFunctionDeclaration8_es2017.types
index 3e46e59409b83..92d7335fd54e0 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration8_es2017.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration8_es2017.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/async/es2017/functionDeclarations/asyncFunctionDeclaration8_es2017.ts ===
 var v = { [await]: foo }
->v : { [x: number]: any; }
->{ [await]: foo } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ [await]: foo } : { [x: string]: any; }
 >[await] : any
 >await : any
 >foo : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration8_es5.types b/tests/baselines/reference/asyncFunctionDeclaration8_es5.types
index f8647156d1101..65fdadc7696bd 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration8_es5.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration8_es5.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/async/es5/functionDeclarations/asyncFunctionDeclaration8_es5.ts ===
 var v = { [await]: foo }
->v : { [x: number]: any; }
->{ [await]: foo } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ [await]: foo } : { [x: string]: any; }
 >[await] : any
 >await : any
 >foo : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration8_es6.types b/tests/baselines/reference/asyncFunctionDeclaration8_es6.types
index 43a0245c7e0d0..79b594b6734ba 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration8_es6.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration8_es6.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/async/es6/functionDeclarations/asyncFunctionDeclaration8_es6.ts ===
 var v = { [await]: foo }
->v : { [x: number]: any; }
->{ [await]: foo } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ [await]: foo } : { [x: string]: any; }
 >[await] : any
 >await : any
 >foo : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration9_es2017.types b/tests/baselines/reference/asyncFunctionDeclaration9_es2017.types
index 47bab654da440..9fad01b2ae244 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration9_es2017.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration9_es2017.types
@@ -4,8 +4,8 @@ async function foo(): Promise<void> {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration9_es5.types b/tests/baselines/reference/asyncFunctionDeclaration9_es5.types
index a049fbc9faa32..53d2545c8971f 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration9_es5.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration9_es5.types
@@ -4,8 +4,8 @@ async function foo(): Promise<void> {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/asyncFunctionDeclaration9_es6.types b/tests/baselines/reference/asyncFunctionDeclaration9_es6.types
index ad3ad1e7b0e62..789ee0d5ee3ab 100644
--- a/tests/baselines/reference/asyncFunctionDeclaration9_es6.types
+++ b/tests/baselines/reference/asyncFunctionDeclaration9_es6.types
@@ -4,8 +4,8 @@ async function foo(): Promise<void> {
 >Promise : Promise<T>
 
   var v = { [await]: foo }
->v : { [x: number]: () => Promise<void>; }
->{ [await]: foo } : { [x: number]: () => Promise<void>; }
+>v : { [x: string]: () => Promise<void>; }
+>{ [await]: foo } : { [x: string]: () => Promise<void>; }
 >[await] : () => Promise<void>
 >await : any
 > : any
diff --git a/tests/baselines/reference/complexRecursiveCollections.types b/tests/baselines/reference/complexRecursiveCollections.types
index d29a9956e194d..f8203b1b4788d 100644
--- a/tests/baselines/reference/complexRecursiveCollections.types
+++ b/tests/baselines/reference/complexRecursiveCollections.types
@@ -1909,9 +1909,9 @@ declare module Immutable {
 
       [Symbol.iterator](): IterableIterator<[keyof T, T[keyof T]]>;
 >[Symbol.iterator] : () => IterableIterator<[keyof T, T[keyof T]]>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >IterableIterator : IterableIterator<T>
 >T : T
 >T : T
@@ -2736,9 +2736,9 @@ declare module Immutable {
 
       [Symbol.iterator](): IterableIterator<[K, V]>;
 >[Symbol.iterator] : () => IterableIterator<[K, V]>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >IterableIterator : IterableIterator<T>
 >K : K
 >V : V
@@ -2980,9 +2980,9 @@ declare module Immutable {
 
       [Symbol.iterator](): IterableIterator<T>;
 >[Symbol.iterator] : () => IterableIterator<T>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >IterableIterator : IterableIterator<T>
 >T : T
     }
@@ -3090,9 +3090,9 @@ declare module Immutable {
 
       [Symbol.iterator](): IterableIterator<T>;
 >[Symbol.iterator] : () => IterableIterator<T>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >IterableIterator : IterableIterator<T>
 >T : T
     }
diff --git a/tests/baselines/reference/computedPropertiesInDestructuring1.types b/tests/baselines/reference/computedPropertiesInDestructuring1.types
index a8605d2a42c21..f57a6e4a95a1c 100644
--- a/tests/baselines/reference/computedPropertiesInDestructuring1.types
+++ b/tests/baselines/reference/computedPropertiesInDestructuring1.types
@@ -163,8 +163,8 @@ let [{[foo.toExponential()]: bar7}] = [{bar: "bar"}];
 
 [{[foo()]: bar4}] = [{bar: "bar"}];
 >[{[foo()]: bar4}] = [{bar: "bar"}] : [{ bar: string; }]
->[{[foo()]: bar4}] : [{ [x: number]: any; }]
->{[foo()]: bar4} : { [x: number]: any; }
+>[{[foo()]: bar4}] : [{ [x: string]: any; }]
+>{[foo()]: bar4} : { [x: string]: any; }
 >[foo()] : any
 >foo() : any
 >foo : string
@@ -176,8 +176,8 @@ let [{[foo.toExponential()]: bar7}] = [{bar: "bar"}];
 
 [{[(1 + {})]: bar4}] = [{bar: "bar"}];
 >[{[(1 + {})]: bar4}] = [{bar: "bar"}] : [{ bar: string; }]
->[{[(1 + {})]: bar4}] : [{ [x: number]: any; }]
->{[(1 + {})]: bar4} : { [x: number]: any; }
+>[{[(1 + {})]: bar4}] : [{ [x: string]: any; }]
+>{[(1 + {})]: bar4} : { [x: string]: any; }
 >[(1 + {})] : any
 >(1 + {}) : any
 >1 + {} : any
diff --git a/tests/baselines/reference/computedPropertiesInDestructuring1_ES6.types b/tests/baselines/reference/computedPropertiesInDestructuring1_ES6.types
index 1a88bc0358db7..240440cceb4b1 100644
--- a/tests/baselines/reference/computedPropertiesInDestructuring1_ES6.types
+++ b/tests/baselines/reference/computedPropertiesInDestructuring1_ES6.types
@@ -170,8 +170,8 @@ let [{[foo.toExponential()]: bar7}] = [{bar: "bar"}];
 
 [{[foo()]: bar4}] = [{bar: "bar"}];
 >[{[foo()]: bar4}] = [{bar: "bar"}] : [{ bar: string; }]
->[{[foo()]: bar4}] : [{ [x: number]: any; }]
->{[foo()]: bar4} : { [x: number]: any; }
+>[{[foo()]: bar4}] : [{ [x: string]: any; }]
+>{[foo()]: bar4} : { [x: string]: any; }
 >[foo()] : any
 >foo() : any
 >foo : string
@@ -183,8 +183,8 @@ let [{[foo.toExponential()]: bar7}] = [{bar: "bar"}];
 
 [{[(1 + {})]: bar4}] = [{bar: "bar"}];
 >[{[(1 + {})]: bar4}] = [{bar: "bar"}] : [{ bar: string; }]
->[{[(1 + {})]: bar4}] : [{ [x: number]: any; }]
->{[(1 + {})]: bar4} : { [x: number]: any; }
+>[{[(1 + {})]: bar4}] : [{ [x: string]: any; }]
+>{[(1 + {})]: bar4} : { [x: string]: any; }
 >[(1 + {})] : any
 >(1 + {}) : any
 >1 + {} : any
diff --git a/tests/baselines/reference/computedPropertyNames18_ES5.types b/tests/baselines/reference/computedPropertyNames18_ES5.types
index 893de7a3157b1..6ab24fd81954d 100644
--- a/tests/baselines/reference/computedPropertyNames18_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames18_ES5.types
@@ -3,8 +3,8 @@ function foo() {
 >foo : () => void
 
     var obj = {
->obj : { [x: number]: number; }
->{        [this.bar]: 0    } : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{        [this.bar]: 0    } : { [x: string]: number; }
 
         [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames18_ES6.types b/tests/baselines/reference/computedPropertyNames18_ES6.types
index 37f531a7907ef..f50f2f8a3517d 100644
--- a/tests/baselines/reference/computedPropertyNames18_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames18_ES6.types
@@ -3,8 +3,8 @@ function foo() {
 >foo : () => void
 
     var obj = {
->obj : { [x: number]: number; }
->{        [this.bar]: 0    } : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{        [this.bar]: 0    } : { [x: string]: number; }
 
         [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames19_ES5.types b/tests/baselines/reference/computedPropertyNames19_ES5.types
index 81bf76e4ac3c5..2abbae2716dfa 100644
--- a/tests/baselines/reference/computedPropertyNames19_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames19_ES5.types
@@ -3,8 +3,8 @@ module M {
 >M : typeof M
 
     var obj = {
->obj : { [x: number]: number; }
->{        [this.bar]: 0    } : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{        [this.bar]: 0    } : { [x: string]: number; }
 
         [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames19_ES6.types b/tests/baselines/reference/computedPropertyNames19_ES6.types
index 5dcc6df206aea..e9b738e651186 100644
--- a/tests/baselines/reference/computedPropertyNames19_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames19_ES6.types
@@ -3,8 +3,8 @@ module M {
 >M : typeof M
 
     var obj = {
->obj : { [x: number]: number; }
->{        [this.bar]: 0    } : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{        [this.bar]: 0    } : { [x: string]: number; }
 
         [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames20_ES5.types b/tests/baselines/reference/computedPropertyNames20_ES5.types
index cc0614b3d0b45..2e8acb2d0142f 100644
--- a/tests/baselines/reference/computedPropertyNames20_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames20_ES5.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/computedProperties/computedPropertyNames20_ES5.ts ===
 var obj = {
->obj : { [x: number]: number; }
->{    [this.bar]: 0} : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{    [this.bar]: 0} : { [x: string]: number; }
 
     [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames20_ES6.types b/tests/baselines/reference/computedPropertyNames20_ES6.types
index 5ffc037860e99..99184816fc2b7 100644
--- a/tests/baselines/reference/computedPropertyNames20_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames20_ES6.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/computedProperties/computedPropertyNames20_ES6.ts ===
 var obj = {
->obj : { [x: number]: number; }
->{    [this.bar]: 0} : { [x: number]: number; }
+>obj : { [x: string]: number; }
+>{    [this.bar]: 0} : { [x: string]: number; }
 
     [this.bar]: 0
 >[this.bar] : number
diff --git a/tests/baselines/reference/computedPropertyNames23_ES5.types b/tests/baselines/reference/computedPropertyNames23_ES5.types
index 7090bfa3ba9a0..88bfa0c8cd479 100644
--- a/tests/baselines/reference/computedPropertyNames23_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames23_ES5.types
@@ -13,7 +13,7 @@ class C {
 
         { [this.bar()]: 1 }[0]
 >{ [this.bar()]: 1 }[0] : number
->{ [this.bar()]: 1 } : { [x: number]: number; }
+>{ [this.bar()]: 1 } : { [x: string]: number; }
 >[this.bar()] : number
 >this.bar() : any
 >this.bar : any
diff --git a/tests/baselines/reference/computedPropertyNames23_ES6.types b/tests/baselines/reference/computedPropertyNames23_ES6.types
index 39133196ed42f..7c05c1eac5d45 100644
--- a/tests/baselines/reference/computedPropertyNames23_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames23_ES6.types
@@ -13,7 +13,7 @@ class C {
 
         { [this.bar()]: 1 }[0]
 >{ [this.bar()]: 1 }[0] : number
->{ [this.bar()]: 1 } : { [x: number]: number; }
+>{ [this.bar()]: 1 } : { [x: string]: number; }
 >[this.bar()] : number
 >this.bar() : any
 >this.bar : any
diff --git a/tests/baselines/reference/computedPropertyNames26_ES5.types b/tests/baselines/reference/computedPropertyNames26_ES5.types
index c9bebbd010a9c..429c2abadcf98 100644
--- a/tests/baselines/reference/computedPropertyNames26_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames26_ES5.types
@@ -18,7 +18,7 @@ class C extends Base {
 
         { [super.bar()]: 1 }[0]
 >{ [super.bar()]: 1 }[0] : number
->{ [super.bar()]: 1 } : { [x: number]: number; }
+>{ [super.bar()]: 1 } : { [x: string]: number; }
 >[super.bar()] : number
 >super.bar() : any
 >super.bar : any
diff --git a/tests/baselines/reference/computedPropertyNames26_ES6.types b/tests/baselines/reference/computedPropertyNames26_ES6.types
index 6a4cf5a15e0c9..fa59e87db9ea4 100644
--- a/tests/baselines/reference/computedPropertyNames26_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames26_ES6.types
@@ -20,7 +20,7 @@ class C extends Base {
 
         { [super.bar()]: 1 }[0]
 >{ [super.bar()]: 1 }[0] : number
->{ [super.bar()]: 1 } : { [x: number]: number; }
+>{ [super.bar()]: 1 } : { [x: string]: number; }
 >[super.bar()] : number
 >super.bar() : any
 >super.bar : any
diff --git a/tests/baselines/reference/computedPropertyNames48_ES5.types b/tests/baselines/reference/computedPropertyNames48_ES5.types
index 9a79d2796230e..fb65f6daf6353 100644
--- a/tests/baselines/reference/computedPropertyNames48_ES5.types
+++ b/tests/baselines/reference/computedPropertyNames48_ES5.types
@@ -17,7 +17,7 @@ var a: any;
 extractIndexer({
 >extractIndexer({    [a]: ""}) : string
 >extractIndexer : <T>(p: { [n: number]: T; }) => T
->{    [a]: ""} : { [x: number]: string; }
+>{    [a]: ""} : { [x: string]: string; }
 
     [a]: ""
 >[a] : string
diff --git a/tests/baselines/reference/computedPropertyNames48_ES6.types b/tests/baselines/reference/computedPropertyNames48_ES6.types
index 5be1ae27e5089..6588b3ca7f310 100644
--- a/tests/baselines/reference/computedPropertyNames48_ES6.types
+++ b/tests/baselines/reference/computedPropertyNames48_ES6.types
@@ -17,7 +17,7 @@ var a: any;
 extractIndexer({
 >extractIndexer({    [a]: ""}) : string
 >extractIndexer : <T>(p: { [n: number]: T; }) => T
->{    [a]: ""} : { [x: number]: string; }
+>{    [a]: ""} : { [x: string]: string; }
 
     [a]: ""
 >[a] : string
diff --git a/tests/baselines/reference/decoratorsOnComputedProperties.js b/tests/baselines/reference/decoratorsOnComputedProperties.js
index 2af6b460c0518..d172100241a4f 100644
--- a/tests/baselines/reference/decoratorsOnComputedProperties.js
+++ b/tests/baselines/reference/decoratorsOnComputedProperties.js
@@ -196,7 +196,7 @@ var __decorate = (this && this.__decorate) || function (decorators, target, key,
     else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
     return c > 3 && r && Object.defineProperty(target, key, r), r;
 };
-var _a, _b, _c, _d, _e, _f, _g, _h, _j, _k, _l, _m, _o, _p, _q, _r, _s, _t, _u, _v, _w, _x, _y, _z, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21;
+var _a, _b, _c, _d, _e, _f, _g, _h, _j, _k, _l, _m, _o, _p, _q, _r, _s, _t, _u, _v, _w, _x, _y, _z, _0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, _16, _17, _18, _19, _20, _21, _22, _23, _24, _25, _26, _27, _28, _29, _30, _31, _32, _33, _34, _35, _36, _37, _38, _39, _40, _41, _42, _43, _44, _45, _46, _47, _48, _49, _50, _51;
 function x(o, k) { }
 let i = 0;
 function foo() { return ++i + ""; }
@@ -206,252 +206,256 @@ const fieldNameC = "fieldName3";
 class A {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
-        this["property4"] = 2;
-        this[Symbol.match] = null;
         this[_b] = null;
-        this[_d] = null;
+        this["property4"] = 2;
+        this[_c] = null;
+        this[_e] = null;
+        this[_g] = null;
     }
 }
-foo(), _a = foo(), _b = foo(), _c = fieldNameB, _d = fieldNameC;
+_a = Symbol.toStringTag, _b = Symbol.iterator, Symbol.isConcatSpreadable, _c = Symbol.match, foo(), _d = foo(), _e = foo(), _f = fieldNameB, _g = fieldNameC;
 __decorate([
     x
 ], A.prototype, "property", void 0);
 __decorate([
     x
-], A.prototype, Symbol.toStringTag, void 0);
+], A.prototype, _a, void 0);
 __decorate([
     x
 ], A.prototype, "property2", void 0);
 __decorate([
     x
-], A.prototype, Symbol.iterator, void 0);
+], A.prototype, _b, void 0);
 __decorate([
     x
-], A.prototype, _a, void 0);
+], A.prototype, _d, void 0);
 __decorate([
     x
-], A.prototype, _b, void 0);
+], A.prototype, _e, void 0);
 __decorate([
     x
-], A.prototype, _c, void 0);
+], A.prototype, _f, void 0);
 __decorate([
     x
-], A.prototype, _d, void 0);
-void (_j = class B {
+], A.prototype, _g, void 0);
+void (_q = class B {
         constructor() {
             this["property2"] = 2;
-            this[Symbol.iterator] = null;
+            this[_j] = null;
             this["property4"] = 2;
-            this[Symbol.match] = null;
-            this[_f] = null;
-            this[_h] = null;
+            this[_k] = null;
+            this[_m] = null;
+            this[_p] = null;
         }
     },
+    _h = Symbol.toStringTag,
+    _j = Symbol.iterator,
+    Symbol.isConcatSpreadable,
+    _k = Symbol.match,
     foo(),
-    _e = foo(),
-    _f = foo(),
-    _g = fieldNameB,
-    _h = fieldNameC,
-    _j);
+    _l = foo(),
+    _m = foo(),
+    _o = fieldNameB,
+    _p = fieldNameC,
+    _q);
 class C {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
+        this[_s] = null;
         this["property4"] = 2;
-        this[Symbol.match] = null;
-        this[_l] = null;
-        this[_o] = null;
+        this[_t] = null;
+        this[_v] = null;
+        this[_x] = null;
     }
-    [(foo(), _k = foo(), _l = foo(), _m = fieldNameB, _o = fieldNameC, "some" + "method")]() { }
+    [(_r = Symbol.toStringTag, _s = Symbol.iterator, Symbol.isConcatSpreadable, _t = Symbol.match, foo(), _u = foo(), _v = foo(), _w = fieldNameB, _x = fieldNameC, "some" + "method")]() { }
 }
 __decorate([
     x
 ], C.prototype, "property", void 0);
 __decorate([
     x
-], C.prototype, Symbol.toStringTag, void 0);
+], C.prototype, _r, void 0);
 __decorate([
     x
 ], C.prototype, "property2", void 0);
 __decorate([
     x
-], C.prototype, Symbol.iterator, void 0);
+], C.prototype, _s, void 0);
 __decorate([
     x
-], C.prototype, _k, void 0);
+], C.prototype, _u, void 0);
 __decorate([
     x
-], C.prototype, _l, void 0);
+], C.prototype, _v, void 0);
 __decorate([
     x
-], C.prototype, _m, void 0);
+], C.prototype, _w, void 0);
 __decorate([
     x
-], C.prototype, _o, void 0);
+], C.prototype, _x, void 0);
 void class D {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
+        this[_z] = null;
         this["property4"] = 2;
-        this[Symbol.match] = null;
-        this[_q] = null;
-        this[_s] = null;
+        this[_0] = null;
+        this[_2] = null;
+        this[_4] = null;
     }
-    [(foo(), _p = foo(), _q = foo(), _r = fieldNameB, _s = fieldNameC, "some" + "method")]() { }
+    [(_y = Symbol.toStringTag, _z = Symbol.iterator, Symbol.isConcatSpreadable, _0 = Symbol.match, foo(), _1 = foo(), _2 = foo(), _3 = fieldNameB, _4 = fieldNameC, "some" + "method")]() { }
 };
 class E {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
+        this[_6] = null;
         this["property4"] = 2;
-        this[Symbol.match] = null;
-        this[_u] = null;
-        this[_w] = null;
+        this[_7] = null;
+        this[_9] = null;
+        this[_11] = null;
     }
-    [(foo(), _t = foo(), _u = foo(), "some" + "method")]() { }
+    [(_5 = Symbol.toStringTag, _6 = Symbol.iterator, Symbol.isConcatSpreadable, _7 = Symbol.match, foo(), _8 = foo(), _9 = foo(), "some" + "method")]() { }
 }
-_v = fieldNameB, _w = fieldNameC;
+_10 = fieldNameB, _11 = fieldNameC;
 __decorate([
     x
 ], E.prototype, "property", void 0);
 __decorate([
     x
-], E.prototype, Symbol.toStringTag, void 0);
+], E.prototype, _5, void 0);
 __decorate([
     x
 ], E.prototype, "property2", void 0);
 __decorate([
     x
-], E.prototype, Symbol.iterator, void 0);
+], E.prototype, _6, void 0);
 __decorate([
     x
-], E.prototype, _t, void 0);
+], E.prototype, _8, void 0);
 __decorate([
     x
-], E.prototype, _u, void 0);
+], E.prototype, _9, void 0);
 __decorate([
     x
-], E.prototype, _v, void 0);
+], E.prototype, _10, void 0);
 __decorate([
     x
-], E.prototype, _w, void 0);
-void (_1 = class F {
+], E.prototype, _11, void 0);
+void (_19 = class F {
         constructor() {
             this["property2"] = 2;
-            this[Symbol.iterator] = null;
+            this[_13] = null;
             this["property4"] = 2;
-            this[Symbol.match] = null;
-            this[_y] = null;
-            this[_0] = null;
+            this[_14] = null;
+            this[_16] = null;
+            this[_18] = null;
         }
-        [(foo(), _x = foo(), _y = foo(), "some" + "method")]() { }
+        [(_12 = Symbol.toStringTag, _13 = Symbol.iterator, Symbol.isConcatSpreadable, _14 = Symbol.match, foo(), _15 = foo(), _16 = foo(), "some" + "method")]() { }
     },
-    _z = fieldNameB,
-    _0 = fieldNameC,
-    _1);
+    _17 = fieldNameB,
+    _18 = fieldNameC,
+    _19);
 class G {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
+        this[_21] = null;
         this["property4"] = 2;
-        this[Symbol.match] = null;
-        this[_3] = null;
-        this[_5] = null;
+        this[_22] = null;
+        this[_24] = null;
+        this[_26] = null;
     }
-    [(foo(), _2 = foo(), _3 = foo(), "some" + "method")]() { }
-    [(_4 = fieldNameB, "some" + "method2")]() { }
+    [(_20 = Symbol.toStringTag, _21 = Symbol.iterator, Symbol.isConcatSpreadable, _22 = Symbol.match, foo(), _23 = foo(), _24 = foo(), "some" + "method")]() { }
+    [(_25 = fieldNameB, "some" + "method2")]() { }
 }
-_5 = fieldNameC;
+_26 = fieldNameC;
 __decorate([
     x
 ], G.prototype, "property", void 0);
 __decorate([
     x
-], G.prototype, Symbol.toStringTag, void 0);
+], G.prototype, _20, void 0);
 __decorate([
     x
 ], G.prototype, "property2", void 0);
 __decorate([
     x
-], G.prototype, Symbol.iterator, void 0);
+], G.prototype, _21, void 0);
 __decorate([
     x
-], G.prototype, _2, void 0);
+], G.prototype, _23, void 0);
 __decorate([
     x
-], G.prototype, _3, void 0);
+], G.prototype, _24, void 0);
 __decorate([
     x
-], G.prototype, _4, void 0);
+], G.prototype, _25, void 0);
 __decorate([
     x
-], G.prototype, _5, void 0);
-void (_10 = class H {
+], G.prototype, _26, void 0);
+void (_34 = class H {
         constructor() {
             this["property2"] = 2;
-            this[Symbol.iterator] = null;
+            this[_28] = null;
             this["property4"] = 2;
-            this[Symbol.match] = null;
-            this[_7] = null;
-            this[_9] = null;
+            this[_29] = null;
+            this[_31] = null;
+            this[_33] = null;
         }
-        [(foo(), _6 = foo(), _7 = foo(), "some" + "method")]() { }
-        [(_8 = fieldNameB, "some" + "method2")]() { }
+        [(_27 = Symbol.toStringTag, _28 = Symbol.iterator, Symbol.isConcatSpreadable, _29 = Symbol.match, foo(), _30 = foo(), _31 = foo(), "some" + "method")]() { }
+        [(_32 = fieldNameB, "some" + "method2")]() { }
     },
-    _9 = fieldNameC,
-    _10);
+    _33 = fieldNameC,
+    _34);
 class I {
     constructor() {
         this["property2"] = 2;
-        this[Symbol.iterator] = null;
+        this[_36] = null;
         this["property4"] = 2;
-        this[Symbol.match] = null;
-        this[_12] = null;
-        this[_15] = null;
+        this[_37] = null;
+        this[_39] = null;
+        this[_42] = null;
     }
-    [(foo(), _11 = foo(), _12 = foo(), _13 = "some" + "method")]() { }
-    [(_14 = fieldNameB, "some" + "method2")]() { }
+    [(_35 = Symbol.toStringTag, _36 = Symbol.iterator, Symbol.isConcatSpreadable, _37 = Symbol.match, foo(), _38 = foo(), _39 = foo(), _40 = "some" + "method")]() { }
+    [(_41 = fieldNameB, "some" + "method2")]() { }
 }
-_15 = fieldNameC;
+_42 = fieldNameC;
 __decorate([
     x
 ], I.prototype, "property", void 0);
 __decorate([
     x
-], I.prototype, Symbol.toStringTag, void 0);
+], I.prototype, _35, void 0);
 __decorate([
     x
 ], I.prototype, "property2", void 0);
 __decorate([
     x
-], I.prototype, Symbol.iterator, void 0);
+], I.prototype, _36, void 0);
 __decorate([
     x
-], I.prototype, _11, void 0);
+], I.prototype, _38, void 0);
 __decorate([
     x
-], I.prototype, _12, void 0);
+], I.prototype, _39, void 0);
 __decorate([
     x
-], I.prototype, _13, null);
+], I.prototype, _40, null);
 __decorate([
     x
-], I.prototype, _14, void 0);
+], I.prototype, _41, void 0);
 __decorate([
     x
-], I.prototype, _15, void 0);
-void (_21 = class J {
+], I.prototype, _42, void 0);
+void (_51 = class J {
         constructor() {
             this["property2"] = 2;
-            this[Symbol.iterator] = null;
+            this[_44] = null;
             this["property4"] = 2;
-            this[Symbol.match] = null;
-            this[_17] = null;
-            this[_20] = null;
+            this[_45] = null;
+            this[_47] = null;
+            this[_50] = null;
         }
-        [(foo(), _16 = foo(), _17 = foo(), _18 = "some" + "method")]() { }
-        [(_19 = fieldNameB, "some" + "method2")]() { }
+        [(_43 = Symbol.toStringTag, _44 = Symbol.iterator, Symbol.isConcatSpreadable, _45 = Symbol.match, foo(), _46 = foo(), _47 = foo(), _48 = "some" + "method")]() { }
+        [(_49 = fieldNameB, "some" + "method2")]() { }
     },
-    _20 = fieldNameC,
-    _21);
+    _50 = fieldNameC,
+    _51);
diff --git a/tests/baselines/reference/decoratorsOnComputedProperties.types b/tests/baselines/reference/decoratorsOnComputedProperties.types
index efbf9c5d2631b..a95abf1ffcbcd 100644
--- a/tests/baselines/reference/decoratorsOnComputedProperties.types
+++ b/tests/baselines/reference/decoratorsOnComputedProperties.types
@@ -39,9 +39,9 @@ class A {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -52,9 +52,9 @@ class A {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -63,9 +63,9 @@ class A {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -74,9 +74,9 @@ class A {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -126,9 +126,9 @@ void class B {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -139,9 +139,9 @@ void class B {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -150,9 +150,9 @@ void class B {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -161,9 +161,9 @@ void class B {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -212,9 +212,9 @@ class C {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -225,9 +225,9 @@ class C {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -236,9 +236,9 @@ class C {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -247,9 +247,9 @@ class C {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -305,9 +305,9 @@ void class D {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -318,9 +318,9 @@ void class D {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -329,9 +329,9 @@ void class D {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -340,9 +340,9 @@ void class D {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -397,9 +397,9 @@ class E {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -410,9 +410,9 @@ class E {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -421,9 +421,9 @@ class E {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -432,9 +432,9 @@ class E {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -490,9 +490,9 @@ void class F {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -503,9 +503,9 @@ void class F {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -514,9 +514,9 @@ void class F {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -525,9 +525,9 @@ void class F {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -582,9 +582,9 @@ class G {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -595,9 +595,9 @@ class G {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -606,9 +606,9 @@ class G {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -617,9 +617,9 @@ class G {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -681,9 +681,9 @@ void class H {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -694,9 +694,9 @@ void class H {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -705,9 +705,9 @@ void class H {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -716,9 +716,9 @@ void class H {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -779,9 +779,9 @@ class I {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -792,9 +792,9 @@ class I {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -803,9 +803,9 @@ class I {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -814,9 +814,9 @@ class I {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
@@ -879,9 +879,9 @@ void class J {
     @x [Symbol.toStringTag]: any;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     @x ["property2"]: any = 2;
 >x : (o: object, k: string | number | symbol) => void
@@ -892,9 +892,9 @@ void class J {
     @x [Symbol.iterator]: any = null;
 >x : (o: object, k: string | number | symbol) => void
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >null : null
 
     ["property3"]: any;
@@ -903,9 +903,9 @@ void class J {
 
     [Symbol.isConcatSpreadable]: any;
 >[Symbol.isConcatSpreadable] : any
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     ["property4"]: any = 2;
 >["property4"] : any
@@ -914,9 +914,9 @@ void class J {
 
     [Symbol.match]: any = null;
 >[Symbol.match] : any
->Symbol.match : symbol
+>Symbol.match : unique symbol
 >Symbol : SymbolConstructor
->match : symbol
+>match : unique symbol
 >null : null
 
     [foo()]: any;
diff --git a/tests/baselines/reference/destructuredLateBoundNameHasCorrectTypes.types b/tests/baselines/reference/destructuredLateBoundNameHasCorrectTypes.types
index 8d24b45e0ec0f..146aa7a32957d 100644
--- a/tests/baselines/reference/destructuredLateBoundNameHasCorrectTypes.types
+++ b/tests/baselines/reference/destructuredLateBoundNameHasCorrectTypes.types
@@ -1,8 +1,8 @@
 === tests/cases/compiler/destructuredLateBoundNameHasCorrectTypes.ts ===
 let { [Symbol.iterator]: destructured } = [];
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >destructured : () => IterableIterator<undefined>
 >[] : undefined[]
 
diff --git a/tests/baselines/reference/es5-asyncFunctionObjectLiterals.types b/tests/baselines/reference/es5-asyncFunctionObjectLiterals.types
index b594e1ba35ad1..24ad1c9f28cc3 100644
--- a/tests/baselines/reference/es5-asyncFunctionObjectLiterals.types
+++ b/tests/baselines/reference/es5-asyncFunctionObjectLiterals.types
@@ -51,9 +51,9 @@ async function objectLiteral2() {
 >objectLiteral2 : () => Promise<void>
 
     x = {
->x = {        [await a]: y,        b: z    } : { [x: number]: any; b: any; }
+>x = {        [await a]: y,        b: z    } : { [x: string]: any; b: any; }
 >x : any
->{        [await a]: y,        b: z    } : { [x: number]: any; b: any; }
+>{        [await a]: y,        b: z    } : { [x: string]: any; b: any; }
 
         [await a]: y,
 >[await a] : any
@@ -72,9 +72,9 @@ async function objectLiteral3() {
 >objectLiteral3 : () => Promise<void>
 
     x = {
->x = {        [a]: await y,        b: z    } : { [x: number]: any; b: any; }
+>x = {        [a]: await y,        b: z    } : { [x: string]: any; b: any; }
 >x : any
->{        [a]: await y,        b: z    } : { [x: number]: any; b: any; }
+>{        [a]: await y,        b: z    } : { [x: string]: any; b: any; }
 
         [a]: await y,
 >[a] : any
@@ -93,9 +93,9 @@ async function objectLiteral4() {
 >objectLiteral4 : () => Promise<void>
 
     x = {
->x = {        a: await y,        [b]: z    } : { [x: number]: any; a: any; }
+>x = {        a: await y,        [b]: z    } : { [x: string]: any; a: any; }
 >x : any
->{        a: await y,        [b]: z    } : { [x: number]: any; a: any; }
+>{        a: await y,        [b]: z    } : { [x: string]: any; a: any; }
 
         a: await y,
 >a : any
@@ -114,9 +114,9 @@ async function objectLiteral5() {
 >objectLiteral5 : () => Promise<void>
 
     x = {
->x = {        a: y,        [await b]: z    } : { [x: number]: any; a: any; }
+>x = {        a: y,        [await b]: z    } : { [x: string]: any; a: any; }
 >x : any
->{        a: y,        [await b]: z    } : { [x: number]: any; a: any; }
+>{        a: y,        [await b]: z    } : { [x: string]: any; a: any; }
 
         a: y,
 >a : any
@@ -135,9 +135,9 @@ async function objectLiteral6() {
 >objectLiteral6 : () => Promise<void>
 
     x = {
->x = {        a: y,        [b]: await z    } : { [x: number]: any; a: any; }
+>x = {        a: y,        [b]: await z    } : { [x: string]: any; a: any; }
 >x : any
->{        a: y,        [b]: await z    } : { [x: number]: any; a: any; }
+>{        a: y,        [b]: await z    } : { [x: string]: any; a: any; }
 
         a: y,
 >a : any
diff --git a/tests/baselines/reference/for-of15.types b/tests/baselines/reference/for-of15.types
index 3ad50870a11ad..130e2c21c7203 100644
--- a/tests/baselines/reference/for-of15.types
+++ b/tests/baselines/reference/for-of15.types
@@ -10,9 +10,9 @@ class StringIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of16.types b/tests/baselines/reference/for-of16.types
index 0396cf215d288..2fb955fec59ff 100644
--- a/tests/baselines/reference/for-of16.types
+++ b/tests/baselines/reference/for-of16.types
@@ -4,9 +4,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of17.types b/tests/baselines/reference/for-of17.types
index 98768f241bac6..be08586182507 100644
--- a/tests/baselines/reference/for-of17.types
+++ b/tests/baselines/reference/for-of17.types
@@ -20,9 +20,9 @@ class NumberIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of18.types b/tests/baselines/reference/for-of18.types
index de784f5ec0d05..643afccd73745 100644
--- a/tests/baselines/reference/for-of18.types
+++ b/tests/baselines/reference/for-of18.types
@@ -20,9 +20,9 @@ class StringIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of19.types b/tests/baselines/reference/for-of19.types
index 2f9620e45aa8e..04a7180dfad90 100644
--- a/tests/baselines/reference/for-of19.types
+++ b/tests/baselines/reference/for-of19.types
@@ -24,9 +24,9 @@ class FooIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of20.types b/tests/baselines/reference/for-of20.types
index d94c056899237..1261375e897c8 100644
--- a/tests/baselines/reference/for-of20.types
+++ b/tests/baselines/reference/for-of20.types
@@ -24,9 +24,9 @@ class FooIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of21.types b/tests/baselines/reference/for-of21.types
index fa6a26466d412..e499da668650d 100644
--- a/tests/baselines/reference/for-of21.types
+++ b/tests/baselines/reference/for-of21.types
@@ -24,9 +24,9 @@ class FooIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of22.types b/tests/baselines/reference/for-of22.types
index 7a6da8a8f604c..524aafb6c6f07 100644
--- a/tests/baselines/reference/for-of22.types
+++ b/tests/baselines/reference/for-of22.types
@@ -24,9 +24,9 @@ class FooIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of23.types b/tests/baselines/reference/for-of23.types
index a88b5162b503d..ca817cb7625af 100644
--- a/tests/baselines/reference/for-of23.types
+++ b/tests/baselines/reference/for-of23.types
@@ -24,9 +24,9 @@ class FooIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of25.types b/tests/baselines/reference/for-of25.types
index 5cc40748bb071..3eb43b9bf7325 100644
--- a/tests/baselines/reference/for-of25.types
+++ b/tests/baselines/reference/for-of25.types
@@ -4,9 +4,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return x;
 >x : any
diff --git a/tests/baselines/reference/for-of26.types b/tests/baselines/reference/for-of26.types
index 5209b1856b38f..bfe34a0488d95 100644
--- a/tests/baselines/reference/for-of26.types
+++ b/tests/baselines/reference/for-of26.types
@@ -10,9 +10,9 @@ class StringIterator {
     }
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of27.js b/tests/baselines/reference/for-of27.js
index 6adc66e241b2b..0845c03bc64b8 100644
--- a/tests/baselines/reference/for-of27.js
+++ b/tests/baselines/reference/for-of27.js
@@ -8,4 +8,5 @@ for (var v of new StringIterator) { }
 //// [for-of27.js]
 class StringIterator {
 }
+Symbol.iterator;
 for (var v of new StringIterator) { }
diff --git a/tests/baselines/reference/for-of27.types b/tests/baselines/reference/for-of27.types
index c72d306c18765..f3db042cdbf00 100644
--- a/tests/baselines/reference/for-of27.types
+++ b/tests/baselines/reference/for-of27.types
@@ -4,9 +4,9 @@ class StringIterator {
 
     [Symbol.iterator]: any;
 >[Symbol.iterator] : any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 }
 
 for (var v of new StringIterator) { }
diff --git a/tests/baselines/reference/for-of28.types b/tests/baselines/reference/for-of28.types
index d1f95753722a8..d9e2099119fd9 100644
--- a/tests/baselines/reference/for-of28.types
+++ b/tests/baselines/reference/for-of28.types
@@ -7,9 +7,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of29.types b/tests/baselines/reference/for-of29.types
index 23d7f986add76..dde2bbee81e99 100644
--- a/tests/baselines/reference/for-of29.types
+++ b/tests/baselines/reference/for-of29.types
@@ -4,9 +4,9 @@ var iterableWithOptionalIterator: {
 
     [Symbol.iterator]?(): Iterator<string>
 >[Symbol.iterator] : () => Iterator<string>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >Iterator : Iterator<T>
 
 };
diff --git a/tests/baselines/reference/for-of30.types b/tests/baselines/reference/for-of30.types
index bd369223d7f5f..861ecdc15c55e 100644
--- a/tests/baselines/reference/for-of30.types
+++ b/tests/baselines/reference/for-of30.types
@@ -24,9 +24,9 @@ class StringIterator {
     
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of31.types b/tests/baselines/reference/for-of31.types
index 843ce928c44e1..a01708c377a15 100644
--- a/tests/baselines/reference/for-of31.types
+++ b/tests/baselines/reference/for-of31.types
@@ -17,9 +17,9 @@ class StringIterator {
     
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of33.types b/tests/baselines/reference/for-of33.types
index 1410ee0653505..0b148994963c2 100644
--- a/tests/baselines/reference/for-of33.types
+++ b/tests/baselines/reference/for-of33.types
@@ -4,9 +4,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => any
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return v;
 >v : any
diff --git a/tests/baselines/reference/for-of34.types b/tests/baselines/reference/for-of34.types
index 5a4287e7843dd..5f5af23648b06 100644
--- a/tests/baselines/reference/for-of34.types
+++ b/tests/baselines/reference/for-of34.types
@@ -11,9 +11,9 @@ class StringIterator {
     
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/for-of35.types b/tests/baselines/reference/for-of35.types
index 0c80a6633b28a..701cced9157d3 100644
--- a/tests/baselines/reference/for-of35.types
+++ b/tests/baselines/reference/for-of35.types
@@ -20,9 +20,9 @@ class StringIterator {
     
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/generatorES6_6.types b/tests/baselines/reference/generatorES6_6.types
index 7306b6ed99ae4..501ac848e1a91 100644
--- a/tests/baselines/reference/generatorES6_6.types
+++ b/tests/baselines/reference/generatorES6_6.types
@@ -4,9 +4,9 @@ class C {
 
   *[Symbol.iterator]() {
 >[Symbol.iterator] : () => IterableIterator<number>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
     let a = yield 1;
 >a : any
diff --git a/tests/baselines/reference/generatorTypeCheck28.types b/tests/baselines/reference/generatorTypeCheck28.types
index fcbae6b76c887..b102cb8d4ec96 100644
--- a/tests/baselines/reference/generatorTypeCheck28.types
+++ b/tests/baselines/reference/generatorTypeCheck28.types
@@ -10,9 +10,9 @@ function* g(): IterableIterator<(x: string) => number> {
 
         *[Symbol.iterator]() {
 >[Symbol.iterator] : () => IterableIterator<(x: string) => number>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
             yield x => x.length;
 >yield x => x.length : any
diff --git a/tests/baselines/reference/generatorTypeCheck41.types b/tests/baselines/reference/generatorTypeCheck41.types
index 5f20d01765582..0d0530945fbb6 100644
--- a/tests/baselines/reference/generatorTypeCheck41.types
+++ b/tests/baselines/reference/generatorTypeCheck41.types
@@ -3,8 +3,8 @@ function* g() {
 >g : () => IterableIterator<number>
 
     let x = {
->x : { [x: number]: number; }
->{        [yield 0]: 0    } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{        [yield 0]: 0    } : { [x: string]: number; }
 
         [yield 0]: 0
 >[yield 0] : number
diff --git a/tests/baselines/reference/generatorTypeCheck42.types b/tests/baselines/reference/generatorTypeCheck42.types
index 47d948739f10d..626da06b02d52 100644
--- a/tests/baselines/reference/generatorTypeCheck42.types
+++ b/tests/baselines/reference/generatorTypeCheck42.types
@@ -3,8 +3,8 @@ function* g() {
 >g : () => IterableIterator<number>
 
     let x = {
->x : { [x: number]: () => void; }
->{        [yield 0]() {        }    } : { [x: number]: () => void; }
+>x : { [x: string]: () => void; }
+>{        [yield 0]() {        }    } : { [x: string]: () => void; }
 
         [yield 0]() {
 >[yield 0] : () => void
diff --git a/tests/baselines/reference/generatorTypeCheck43.types b/tests/baselines/reference/generatorTypeCheck43.types
index 298c631728ebb..8e5fd32408ba5 100644
--- a/tests/baselines/reference/generatorTypeCheck43.types
+++ b/tests/baselines/reference/generatorTypeCheck43.types
@@ -3,8 +3,8 @@ function* g() {
 >g : () => IterableIterator<number>
 
     let x = {
->x : { [x: number]: () => IterableIterator<any>; }
->{        *[yield 0]() {        }    } : { [x: number]: () => IterableIterator<any>; }
+>x : { [x: string]: () => IterableIterator<any>; }
+>{        *[yield 0]() {        }    } : { [x: string]: () => IterableIterator<any>; }
 
         *[yield 0]() {
 >[yield 0] : () => IterableIterator<any>
diff --git a/tests/baselines/reference/generatorTypeCheck44.types b/tests/baselines/reference/generatorTypeCheck44.types
index 38b335f1ab46c..a21f0569987cc 100644
--- a/tests/baselines/reference/generatorTypeCheck44.types
+++ b/tests/baselines/reference/generatorTypeCheck44.types
@@ -3,8 +3,8 @@ function* g() {
 >g : () => IterableIterator<number>
 
     let x = {
->x : { [x: number]: number; }
->{        get [yield 0]() {            return 0;        }    } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{        get [yield 0]() {            return 0;        }    } : { [x: string]: number; }
 
         get [yield 0]() {
 >[yield 0] : number
diff --git a/tests/baselines/reference/generatorTypeCheck46.types b/tests/baselines/reference/generatorTypeCheck46.types
index ea96133000c31..08b2af1adb1df 100644
--- a/tests/baselines/reference/generatorTypeCheck46.types
+++ b/tests/baselines/reference/generatorTypeCheck46.types
@@ -28,9 +28,9 @@ foo("", function* () {
 
         *[Symbol.iterator]() {
 >[Symbol.iterator] : () => IterableIterator<(x: string) => number>
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
             yield x => x.length
 >yield x => x.length : any
diff --git a/tests/baselines/reference/intersectionTypeInference3.types b/tests/baselines/reference/intersectionTypeInference3.types
index 9af8eaf6d0354..c6a471cc27338 100644
--- a/tests/baselines/reference/intersectionTypeInference3.types
+++ b/tests/baselines/reference/intersectionTypeInference3.types
@@ -9,9 +9,9 @@ type Nominal<Kind extends string, Type> = Type & {
 
     [Symbol.species]: Kind;
 >[Symbol.species] : Kind
->Symbol.species : symbol
+>Symbol.species : unique symbol
 >Symbol : SymbolConstructor
->species : symbol
+>species : unique symbol
 >Kind : Kind
 
 };
diff --git a/tests/baselines/reference/invalidNewTarget.es5.types b/tests/baselines/reference/invalidNewTarget.es5.types
index 5a7703b684462..e3cc854aaeb94 100644
--- a/tests/baselines/reference/invalidNewTarget.es5.types
+++ b/tests/baselines/reference/invalidNewTarget.es5.types
@@ -73,8 +73,8 @@ class C {
 }
 
 const O = {
->O : { [x: number]: any; k(): any; readonly l: any; m: any; n: any; }
->{    [new.target]: undefined,    k() { return new.target; },    get l() { return new.target; },    set m(_) { _ = new.target; },    n: new.target,} : { [x: number]: undefined; k(): any; readonly l: any; m: any; n: any; }
+>O : { [x: string]: any; k(): any; readonly l: any; m: any; n: any; }
+>{    [new.target]: undefined,    k() { return new.target; },    get l() { return new.target; },    set m(_) { _ = new.target; },    n: new.target,} : { [x: string]: any; k(): any; readonly l: any; m: any; n: any; }
 
     [new.target]: undefined,
 >[new.target] : undefined
diff --git a/tests/baselines/reference/invalidNewTarget.es6.types b/tests/baselines/reference/invalidNewTarget.es6.types
index a7690f4cbbca8..bb9dfef0bf66d 100644
--- a/tests/baselines/reference/invalidNewTarget.es6.types
+++ b/tests/baselines/reference/invalidNewTarget.es6.types
@@ -73,8 +73,8 @@ class C {
 }
 
 const O = {
->O : { [x: number]: any; k(): any; readonly l: any; m: any; n: any; }
->{    [new.target]: undefined,    k() { return new.target; },    get l() { return new.target; },    set m(_) { _ = new.target; },    n: new.target,} : { [x: number]: undefined; k(): any; readonly l: any; m: any; n: any; }
+>O : { [x: string]: any; k(): any; readonly l: any; m: any; n: any; }
+>{    [new.target]: undefined,    k() { return new.target; },    get l() { return new.target; },    set m(_) { _ = new.target; },    n: new.target,} : { [x: string]: any; k(): any; readonly l: any; m: any; n: any; }
 
     [new.target]: undefined,
 >[new.target] : undefined
diff --git a/tests/baselines/reference/iterableArrayPattern1.types b/tests/baselines/reference/iterableArrayPattern1.types
index 8bdf0ebc6ed15..e9dde480d4749 100644
--- a/tests/baselines/reference/iterableArrayPattern1.types
+++ b/tests/baselines/reference/iterableArrayPattern1.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern10.types b/tests/baselines/reference/iterableArrayPattern10.types
index 2ae11652898da..3f431ac7850b0 100644
--- a/tests/baselines/reference/iterableArrayPattern10.types
+++ b/tests/baselines/reference/iterableArrayPattern10.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern11.types b/tests/baselines/reference/iterableArrayPattern11.types
index 6c9f384aa4fe3..fe7cdd293044b 100644
--- a/tests/baselines/reference/iterableArrayPattern11.types
+++ b/tests/baselines/reference/iterableArrayPattern11.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern12.types b/tests/baselines/reference/iterableArrayPattern12.types
index d55d2f2fecbd6..0280487bbc58f 100644
--- a/tests/baselines/reference/iterableArrayPattern12.types
+++ b/tests/baselines/reference/iterableArrayPattern12.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern13.types b/tests/baselines/reference/iterableArrayPattern13.types
index d73f5cf0ab8de..f6e14c16392ef 100644
--- a/tests/baselines/reference/iterableArrayPattern13.types
+++ b/tests/baselines/reference/iterableArrayPattern13.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern14.types b/tests/baselines/reference/iterableArrayPattern14.types
index b16b7e39c12cb..d364cf7dc8fcf 100644
--- a/tests/baselines/reference/iterableArrayPattern14.types
+++ b/tests/baselines/reference/iterableArrayPattern14.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern15.types b/tests/baselines/reference/iterableArrayPattern15.types
index 7c553927a911a..45cac722e1e1c 100644
--- a/tests/baselines/reference/iterableArrayPattern15.types
+++ b/tests/baselines/reference/iterableArrayPattern15.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern16.types b/tests/baselines/reference/iterableArrayPattern16.types
index a2b0c9a0b6761..b62069ba9ada8 100644
--- a/tests/baselines/reference/iterableArrayPattern16.types
+++ b/tests/baselines/reference/iterableArrayPattern16.types
@@ -45,9 +45,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -77,9 +77,9 @@ class FooIteratorIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern17.types b/tests/baselines/reference/iterableArrayPattern17.types
index 3163269bf8b1a..71db05f28e91a 100644
--- a/tests/baselines/reference/iterableArrayPattern17.types
+++ b/tests/baselines/reference/iterableArrayPattern17.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern18.types b/tests/baselines/reference/iterableArrayPattern18.types
index 1a84ee4af96d4..cdde399d46ec5 100644
--- a/tests/baselines/reference/iterableArrayPattern18.types
+++ b/tests/baselines/reference/iterableArrayPattern18.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern19.types b/tests/baselines/reference/iterableArrayPattern19.types
index dfd45e4a189e0..029dbfdb0b775 100644
--- a/tests/baselines/reference/iterableArrayPattern19.types
+++ b/tests/baselines/reference/iterableArrayPattern19.types
@@ -32,9 +32,9 @@ class FooArrayIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern2.types b/tests/baselines/reference/iterableArrayPattern2.types
index 2dfab111579db..e39bbdd7be709 100644
--- a/tests/baselines/reference/iterableArrayPattern2.types
+++ b/tests/baselines/reference/iterableArrayPattern2.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern20.types b/tests/baselines/reference/iterableArrayPattern20.types
index 542402f741a59..55f4e221ec7a6 100644
--- a/tests/baselines/reference/iterableArrayPattern20.types
+++ b/tests/baselines/reference/iterableArrayPattern20.types
@@ -32,9 +32,9 @@ class FooArrayIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern3.types b/tests/baselines/reference/iterableArrayPattern3.types
index 7d79b7e204613..a7ac464ab8b99 100644
--- a/tests/baselines/reference/iterableArrayPattern3.types
+++ b/tests/baselines/reference/iterableArrayPattern3.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern4.types b/tests/baselines/reference/iterableArrayPattern4.types
index ece3b235dc437..c1bec39d3af41 100644
--- a/tests/baselines/reference/iterableArrayPattern4.types
+++ b/tests/baselines/reference/iterableArrayPattern4.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern5.types b/tests/baselines/reference/iterableArrayPattern5.types
index 708d6c7631afc..57c5a2767f5ae 100644
--- a/tests/baselines/reference/iterableArrayPattern5.types
+++ b/tests/baselines/reference/iterableArrayPattern5.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern6.types b/tests/baselines/reference/iterableArrayPattern6.types
index c465c02ea4494..6ee03db2d997e 100644
--- a/tests/baselines/reference/iterableArrayPattern6.types
+++ b/tests/baselines/reference/iterableArrayPattern6.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern7.types b/tests/baselines/reference/iterableArrayPattern7.types
index 4d00cb6d61019..05a70c9ab9850 100644
--- a/tests/baselines/reference/iterableArrayPattern7.types
+++ b/tests/baselines/reference/iterableArrayPattern7.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern8.types b/tests/baselines/reference/iterableArrayPattern8.types
index 7614b15b05494..046a4bab5fcad 100644
--- a/tests/baselines/reference/iterableArrayPattern8.types
+++ b/tests/baselines/reference/iterableArrayPattern8.types
@@ -31,9 +31,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iterableArrayPattern9.types b/tests/baselines/reference/iterableArrayPattern9.types
index ca9ced3e787d9..94a4e33ea69f8 100644
--- a/tests/baselines/reference/iterableArrayPattern9.types
+++ b/tests/baselines/reference/iterableArrayPattern9.types
@@ -38,9 +38,9 @@ class FooIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray.types b/tests/baselines/reference/iteratorSpreadInArray.types
index 1b0f6954f71b2..c71ad753d1ba5 100644
--- a/tests/baselines/reference/iteratorSpreadInArray.types
+++ b/tests/baselines/reference/iteratorSpreadInArray.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray10.types b/tests/baselines/reference/iteratorSpreadInArray10.types
index dd6bec4bbbd53..364202ec3ec94 100644
--- a/tests/baselines/reference/iteratorSpreadInArray10.types
+++ b/tests/baselines/reference/iteratorSpreadInArray10.types
@@ -4,9 +4,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray2.types b/tests/baselines/reference/iteratorSpreadInArray2.types
index 12eff588816c1..e05f8d4b0bc2b 100644
--- a/tests/baselines/reference/iteratorSpreadInArray2.types
+++ b/tests/baselines/reference/iteratorSpreadInArray2.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -53,9 +53,9 @@ class NumberIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray3.types b/tests/baselines/reference/iteratorSpreadInArray3.types
index 5c32643e302b6..c13d41bd43c68 100644
--- a/tests/baselines/reference/iteratorSpreadInArray3.types
+++ b/tests/baselines/reference/iteratorSpreadInArray3.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray4.types b/tests/baselines/reference/iteratorSpreadInArray4.types
index a6c8a53d320f8..9c5ae99689154 100644
--- a/tests/baselines/reference/iteratorSpreadInArray4.types
+++ b/tests/baselines/reference/iteratorSpreadInArray4.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray5.types b/tests/baselines/reference/iteratorSpreadInArray5.types
index eac7f537f357b..6163460fece06 100644
--- a/tests/baselines/reference/iteratorSpreadInArray5.types
+++ b/tests/baselines/reference/iteratorSpreadInArray5.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray6.types b/tests/baselines/reference/iteratorSpreadInArray6.types
index b964fdbca1304..e97a3f778d856 100644
--- a/tests/baselines/reference/iteratorSpreadInArray6.types
+++ b/tests/baselines/reference/iteratorSpreadInArray6.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray7.types b/tests/baselines/reference/iteratorSpreadInArray7.types
index 9d3cf2cfa7ed6..11dfaeb872c00 100644
--- a/tests/baselines/reference/iteratorSpreadInArray7.types
+++ b/tests/baselines/reference/iteratorSpreadInArray7.types
@@ -22,9 +22,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInArray9.types b/tests/baselines/reference/iteratorSpreadInArray9.types
index 82e4064526afa..1cac23527eae5 100644
--- a/tests/baselines/reference/iteratorSpreadInArray9.types
+++ b/tests/baselines/reference/iteratorSpreadInArray9.types
@@ -18,9 +18,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall.types b/tests/baselines/reference/iteratorSpreadInCall.types
index fc971f24f5e89..9d369c853f89c 100644
--- a/tests/baselines/reference/iteratorSpreadInCall.types
+++ b/tests/baselines/reference/iteratorSpreadInCall.types
@@ -26,9 +26,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall10.types b/tests/baselines/reference/iteratorSpreadInCall10.types
index 373f5c24a0af9..951965a1546a3 100644
--- a/tests/baselines/reference/iteratorSpreadInCall10.types
+++ b/tests/baselines/reference/iteratorSpreadInCall10.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall11.types b/tests/baselines/reference/iteratorSpreadInCall11.types
index 2407ba1c4a56a..09d3b759ec6a9 100644
--- a/tests/baselines/reference/iteratorSpreadInCall11.types
+++ b/tests/baselines/reference/iteratorSpreadInCall11.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall12.types b/tests/baselines/reference/iteratorSpreadInCall12.types
index e346ea0f358ce..0d687e18c262f 100644
--- a/tests/baselines/reference/iteratorSpreadInCall12.types
+++ b/tests/baselines/reference/iteratorSpreadInCall12.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -62,9 +62,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall2.types b/tests/baselines/reference/iteratorSpreadInCall2.types
index 4ffcf0b01de97..94ad7d780b682 100644
--- a/tests/baselines/reference/iteratorSpreadInCall2.types
+++ b/tests/baselines/reference/iteratorSpreadInCall2.types
@@ -26,9 +26,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall3.types b/tests/baselines/reference/iteratorSpreadInCall3.types
index 8c629fc2d7623..570fbd6892a56 100644
--- a/tests/baselines/reference/iteratorSpreadInCall3.types
+++ b/tests/baselines/reference/iteratorSpreadInCall3.types
@@ -26,9 +26,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall4.types b/tests/baselines/reference/iteratorSpreadInCall4.types
index 56968f87094e1..2ac3d6b455391 100644
--- a/tests/baselines/reference/iteratorSpreadInCall4.types
+++ b/tests/baselines/reference/iteratorSpreadInCall4.types
@@ -27,9 +27,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall5.types b/tests/baselines/reference/iteratorSpreadInCall5.types
index 5d70581cacb8c..c2f03f21f9afe 100644
--- a/tests/baselines/reference/iteratorSpreadInCall5.types
+++ b/tests/baselines/reference/iteratorSpreadInCall5.types
@@ -26,9 +26,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -57,9 +57,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall6.types b/tests/baselines/reference/iteratorSpreadInCall6.types
index 6a040d25e6d15..98370183afc07 100644
--- a/tests/baselines/reference/iteratorSpreadInCall6.types
+++ b/tests/baselines/reference/iteratorSpreadInCall6.types
@@ -26,9 +26,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -57,9 +57,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall7.types b/tests/baselines/reference/iteratorSpreadInCall7.types
index 953ee50c8d939..8746679bb499c 100644
--- a/tests/baselines/reference/iteratorSpreadInCall7.types
+++ b/tests/baselines/reference/iteratorSpreadInCall7.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -62,9 +62,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall8.types b/tests/baselines/reference/iteratorSpreadInCall8.types
index ea404bdde5bb7..7e4cd222fc526 100644
--- a/tests/baselines/reference/iteratorSpreadInCall8.types
+++ b/tests/baselines/reference/iteratorSpreadInCall8.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -62,9 +62,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/iteratorSpreadInCall9.types b/tests/baselines/reference/iteratorSpreadInCall9.types
index 270db4cd3cf94..78cb58a6a1c2b 100644
--- a/tests/baselines/reference/iteratorSpreadInCall9.types
+++ b/tests/baselines/reference/iteratorSpreadInCall9.types
@@ -31,9 +31,9 @@ class SymbolIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
@@ -62,9 +62,9 @@ class StringIterator {
 
     [Symbol.iterator]() {
 >[Symbol.iterator] : () => this
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
         return this;
 >this : this
diff --git a/tests/baselines/reference/modularizeLibrary_ErrorFromUsingES6FeaturesWithOnlyES5Lib.types b/tests/baselines/reference/modularizeLibrary_ErrorFromUsingES6FeaturesWithOnlyES5Lib.types
index 6081b16c835d6..2101d8a93ac22 100644
--- a/tests/baselines/reference/modularizeLibrary_ErrorFromUsingES6FeaturesWithOnlyES5Lib.types
+++ b/tests/baselines/reference/modularizeLibrary_ErrorFromUsingES6FeaturesWithOnlyES5Lib.types
@@ -60,8 +60,8 @@ Math.sign(1);
 
 // Using ES6 object
 var o = {
->o : { a: number; [Symbol.hasInstance](value: any): boolean; }
->{    a: 2,    [Symbol.hasInstance](value: any) {        return false;    }} : { a: number; [Symbol.hasInstance](value: any): boolean; }
+>o : { [x: string]: number | ((value: any) => boolean); a: number; }
+>{    a: 2,    [Symbol.hasInstance](value: any) {        return false;    }} : { [x: string]: number | ((value: any) => boolean); a: number; }
 
     a: 2,
 >a : number
@@ -81,7 +81,7 @@ var o = {
 o.hasOwnProperty(Symbol.hasInstance);
 >o.hasOwnProperty(Symbol.hasInstance) : boolean
 >o.hasOwnProperty : (v: string | number | symbol) => boolean
->o : { a: number; [Symbol.hasInstance](value: any): boolean; }
+>o : { [x: string]: number | ((value: any) => boolean); a: number; }
 >hasOwnProperty : (v: string | number | symbol) => boolean
 >Symbol.hasInstance : any
 >Symbol : any
@@ -140,8 +140,8 @@ var s = Symbol();
 
 // Using ES6 wellknown-symbol
 const o1 = {
->o1 : { [Symbol.hasInstance](value: any): boolean; }
->{    [Symbol.hasInstance](value: any) {        return false;    }} : { [Symbol.hasInstance](value: any): boolean; }
+>o1 : { [x: string]: (value: any) => boolean; }
+>{    [Symbol.hasInstance](value: any) {        return false;    }} : { [x: string]: (value: any) => boolean; }
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
diff --git a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
index 4bfd9b37441ad..4f3abf2a655a8 100644
--- a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
+++ b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions1.types
@@ -113,9 +113,9 @@ var o = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
@@ -127,9 +127,9 @@ o.hasOwnProperty(Symbol.hasInstance);
 >o.hasOwnProperty : (v: string | number | symbol) => boolean
 >o : { a: number; [Symbol.hasInstance](value: any): boolean; }
 >hasOwnProperty : (v: string | number | symbol) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
 // Using ES6 promise
 async function out() {
@@ -221,9 +221,9 @@ const o1 = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
diff --git a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
index cfc9dd398232c..41f0942ca3082 100644
--- a/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
+++ b/tests/baselines/reference/modularizeLibrary_NoErrorDuplicateLibOptions2.types
@@ -113,9 +113,9 @@ var o = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
@@ -127,9 +127,9 @@ o.hasOwnProperty(Symbol.hasInstance);
 >o.hasOwnProperty : (v: string | number | symbol) => boolean
 >o : { a: number; [Symbol.hasInstance](value: any): boolean; }
 >hasOwnProperty : (v: string | number | symbol) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
 // Using ES6 promise
 async function out() {
@@ -221,9 +221,9 @@ const o1 = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
diff --git a/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types b/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
index f9203bbc639e4..db9ad465b2a95 100644
--- a/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
+++ b/tests/baselines/reference/modularizeLibrary_TargetES5UsingES6Lib.types
@@ -113,9 +113,9 @@ var o = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
@@ -127,9 +127,9 @@ o.hasOwnProperty(Symbol.hasInstance);
 >o.hasOwnProperty : (v: string | number | symbol) => boolean
 >o : { a: number; [Symbol.hasInstance](value: any): boolean; }
 >hasOwnProperty : (v: string | number | symbol) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
 // Using ES6 promise
 async function out() {
@@ -221,9 +221,9 @@ const o1 = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
diff --git a/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types b/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
index f4eaba5875235..c1bab6bc537fc 100644
--- a/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
+++ b/tests/baselines/reference/modularizeLibrary_TargetES6UsingES6Lib.types
@@ -68,9 +68,9 @@ var o = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
@@ -82,9 +82,9 @@ o.hasOwnProperty(Symbol.hasInstance);
 >o.hasOwnProperty : (v: string | number | symbol) => boolean
 >o : { a: number; [Symbol.hasInstance](value: any): boolean; }
 >hasOwnProperty : (v: string | number | symbol) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
 // Using Es6 proxy
 var t = {}
@@ -144,9 +144,9 @@ const o1 = {
 
     [Symbol.hasInstance](value: any) {
 >[Symbol.hasInstance] : (value: any) => boolean
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >value : any
 
         return false;
diff --git a/tests/baselines/reference/modularizeLibrary_UsingES5LibES6ArrayLibES6WellknownSymbolLib.types b/tests/baselines/reference/modularizeLibrary_UsingES5LibES6ArrayLibES6WellknownSymbolLib.types
index caca4cf87599a..71fe2fd4f653d 100644
--- a/tests/baselines/reference/modularizeLibrary_UsingES5LibES6ArrayLibES6WellknownSymbolLib.types
+++ b/tests/baselines/reference/modularizeLibrary_UsingES5LibES6ArrayLibES6WellknownSymbolLib.types
@@ -30,8 +30,8 @@ a[Symbol.isConcatSpreadable] = false;
 >a[Symbol.isConcatSpreadable] = false : false
 >a[Symbol.isConcatSpreadable] : any
 >a : string[]
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >false : false
 
diff --git a/tests/baselines/reference/parser.asyncGenerators.classMethods.esnext.types b/tests/baselines/reference/parser.asyncGenerators.classMethods.esnext.types
index 81636f0d9f351..d43b03ae27595 100644
--- a/tests/baselines/reference/parser.asyncGenerators.classMethods.esnext.types
+++ b/tests/baselines/reference/parser.asyncGenerators.classMethods.esnext.types
@@ -253,8 +253,8 @@ class C22 {
 >f : () => AsyncIterableIterator<any>
 
         const x = { [yield]: 1 };
->x : { [x: number]: number; }
->{ [yield]: 1 } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{ [yield]: 1 } : { [x: string]: number; }
 >[yield] : number
 >yield : any
 >1 : 1
diff --git a/tests/baselines/reference/parser.asyncGenerators.functionDeclarations.esnext.types b/tests/baselines/reference/parser.asyncGenerators.functionDeclarations.esnext.types
index d1ec77dd6aef2..cd91c18050c2f 100644
--- a/tests/baselines/reference/parser.asyncGenerators.functionDeclarations.esnext.types
+++ b/tests/baselines/reference/parser.asyncGenerators.functionDeclarations.esnext.types
@@ -160,8 +160,8 @@ async function * f21() {
 >f21 : () => AsyncIterableIterator<any>
 
     const x = { [yield]: 1 };
->x : { [x: number]: number; }
->{ [yield]: 1 } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{ [yield]: 1 } : { [x: string]: number; }
 >[yield] : number
 >yield : any
 >1 : 1
diff --git a/tests/baselines/reference/parser.asyncGenerators.functionExpressions.esnext.types b/tests/baselines/reference/parser.asyncGenerators.functionExpressions.esnext.types
index db905db6509ca..1bd68ae40d123 100644
--- a/tests/baselines/reference/parser.asyncGenerators.functionExpressions.esnext.types
+++ b/tests/baselines/reference/parser.asyncGenerators.functionExpressions.esnext.types
@@ -202,8 +202,8 @@ const f21 = async function *() {
 >async function *() {    const x = { [yield]: 1 };} : () => AsyncIterableIterator<any>
 
     const x = { [yield]: 1 };
->x : { [x: number]: number; }
->{ [yield]: 1 } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{ [yield]: 1 } : { [x: string]: number; }
 >[yield] : number
 >yield : any
 >1 : 1
diff --git a/tests/baselines/reference/parser.asyncGenerators.objectLiteralMethods.esnext.types b/tests/baselines/reference/parser.asyncGenerators.objectLiteralMethods.esnext.types
index 4b159f793fe42..cc4a83ec89670 100644
--- a/tests/baselines/reference/parser.asyncGenerators.objectLiteralMethods.esnext.types
+++ b/tests/baselines/reference/parser.asyncGenerators.objectLiteralMethods.esnext.types
@@ -267,8 +267,8 @@ const o21 = {
 >f : () => AsyncIterableIterator<any>
 
         const x = { [yield]: 1 };
->x : { [x: number]: number; }
->{ [yield]: 1 } : { [x: number]: number; }
+>x : { [x: string]: number; }
+>{ [yield]: 1 } : { [x: string]: number; }
 >[yield] : number
 >yield : any
 >1 : 1
diff --git a/tests/baselines/reference/parserComputedPropertyName1.types b/tests/baselines/reference/parserComputedPropertyName1.types
index 229b345194efc..1b77ff7bb6067 100644
--- a/tests/baselines/reference/parserComputedPropertyName1.types
+++ b/tests/baselines/reference/parserComputedPropertyName1.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName1.ts ===
 var v = { [e] };
->v : { [x: number]: any; }
->{ [e] } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ [e] } : { [x: string]: any; }
 >[e] : any
 >e : any
 > : any
diff --git a/tests/baselines/reference/parserComputedPropertyName17.types b/tests/baselines/reference/parserComputedPropertyName17.types
index 141f36f9455ee..bfe61e79cab83 100644
--- a/tests/baselines/reference/parserComputedPropertyName17.types
+++ b/tests/baselines/reference/parserComputedPropertyName17.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName17.ts ===
 var v = { set [e](v) { } }
->v : { [x: number]: any; }
->{ set [e](v) { } } : { [x: number]: any; }
+>v : { [x: string]: any; }
+>{ set [e](v) { } } : { [x: string]: any; }
 >[e] : any
 >e : any
 >v : any
diff --git a/tests/baselines/reference/parserComputedPropertyName2.types b/tests/baselines/reference/parserComputedPropertyName2.types
index fedfb2ea33ff8..bc1600e4b2b08 100644
--- a/tests/baselines/reference/parserComputedPropertyName2.types
+++ b/tests/baselines/reference/parserComputedPropertyName2.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName2.ts ===
 var v = { [e]: 1 };
->v : { [x: number]: number; }
->{ [e]: 1 } : { [x: number]: number; }
+>v : { [x: string]: number; }
+>{ [e]: 1 } : { [x: string]: number; }
 >[e] : number
 >e : any
 >1 : 1
diff --git a/tests/baselines/reference/parserComputedPropertyName3.types b/tests/baselines/reference/parserComputedPropertyName3.types
index 7a9d4aff23248..981221459cac4 100644
--- a/tests/baselines/reference/parserComputedPropertyName3.types
+++ b/tests/baselines/reference/parserComputedPropertyName3.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName3.ts ===
 var v = { [e]() { } };
->v : { [x: number]: () => void; }
->{ [e]() { } } : { [x: number]: () => void; }
+>v : { [x: string]: () => void; }
+>{ [e]() { } } : { [x: string]: () => void; }
 >[e] : () => void
 >e : any
 
diff --git a/tests/baselines/reference/parserComputedPropertyName37.types b/tests/baselines/reference/parserComputedPropertyName37.types
index c0ef9ee0eb3c3..145108c7d78cc 100644
--- a/tests/baselines/reference/parserComputedPropertyName37.types
+++ b/tests/baselines/reference/parserComputedPropertyName37.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName37.ts ===
 var v = {
->v : { [x: number]: number; }
->{    [public]: 0} : { [x: number]: number; }
+>v : { [x: string]: number; }
+>{    [public]: 0} : { [x: string]: number; }
 
     [public]: 0
 >[public] : number
diff --git a/tests/baselines/reference/parserComputedPropertyName4.types b/tests/baselines/reference/parserComputedPropertyName4.types
index 66ac75b156b26..05065aee5a4d0 100644
--- a/tests/baselines/reference/parserComputedPropertyName4.types
+++ b/tests/baselines/reference/parserComputedPropertyName4.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName4.ts ===
 var v = { get [e]() { } };
->v : { [x: number]: void; }
->{ get [e]() { } } : { [x: number]: void; }
+>v : { [x: string]: void; }
+>{ get [e]() { } } : { [x: string]: void; }
 >[e] : void
 >e : any
 
diff --git a/tests/baselines/reference/parserComputedPropertyName5.types b/tests/baselines/reference/parserComputedPropertyName5.types
index 383f590909fc2..6d5b6dbd23583 100644
--- a/tests/baselines/reference/parserComputedPropertyName5.types
+++ b/tests/baselines/reference/parserComputedPropertyName5.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName5.ts ===
 var v = { public get [e]() { } };
->v : { [x: number]: void; }
->{ public get [e]() { } } : { [x: number]: void; }
+>v : { [x: string]: void; }
+>{ public get [e]() { } } : { [x: string]: void; }
 >[e] : void
 >e : any
 
diff --git a/tests/baselines/reference/parserComputedPropertyName6.types b/tests/baselines/reference/parserComputedPropertyName6.types
index c292156dce011..c15cefd59c2ee 100644
--- a/tests/baselines/reference/parserComputedPropertyName6.types
+++ b/tests/baselines/reference/parserComputedPropertyName6.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/ComputedPropertyNames/parserComputedPropertyName6.ts ===
 var v = { [e]: 1, [e + e]: 2 };
->v : { [x: number]: number; }
->{ [e]: 1, [e + e]: 2 } : { [x: number]: number; }
+>v : { [x: string]: number; }
+>{ [e]: 1, [e + e]: 2 } : { [x: string]: number; }
 >[e] : number
 >e : any
 >1 : 1
diff --git a/tests/baselines/reference/parserES5ComputedPropertyName2.types b/tests/baselines/reference/parserES5ComputedPropertyName2.types
index 6d40c5687e9a7..0aa59a0ccda28 100644
--- a/tests/baselines/reference/parserES5ComputedPropertyName2.types
+++ b/tests/baselines/reference/parserES5ComputedPropertyName2.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript5/ComputedPropertyNames/parserES5ComputedPropertyName2.ts ===
 var v = { [e]: 1 };
->v : { [x: number]: number; }
->{ [e]: 1 } : { [x: number]: number; }
+>v : { [x: string]: number; }
+>{ [e]: 1 } : { [x: string]: number; }
 >[e] : number
 >e : any
 >1 : 1
diff --git a/tests/baselines/reference/parserES5ComputedPropertyName3.types b/tests/baselines/reference/parserES5ComputedPropertyName3.types
index 012ebae6bbf3f..d40de1262582f 100644
--- a/tests/baselines/reference/parserES5ComputedPropertyName3.types
+++ b/tests/baselines/reference/parserES5ComputedPropertyName3.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript5/ComputedPropertyNames/parserES5ComputedPropertyName3.ts ===
 var v = { [e]() { } };
->v : { [x: number]: () => void; }
->{ [e]() { } } : { [x: number]: () => void; }
+>v : { [x: string]: () => void; }
+>{ [e]() { } } : { [x: string]: () => void; }
 >[e] : () => void
 >e : any
 
diff --git a/tests/baselines/reference/parserES5ComputedPropertyName4.types b/tests/baselines/reference/parserES5ComputedPropertyName4.types
index 4e021729a7d8c..160885480944e 100644
--- a/tests/baselines/reference/parserES5ComputedPropertyName4.types
+++ b/tests/baselines/reference/parserES5ComputedPropertyName4.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript5/ComputedPropertyNames/parserES5ComputedPropertyName4.ts ===
 var v = { get [e]() { } };
->v : { [x: number]: void; }
->{ get [e]() { } } : { [x: number]: void; }
+>v : { [x: string]: void; }
+>{ get [e]() { } } : { [x: string]: void; }
 >[e] : void
 >e : any
 
diff --git a/tests/baselines/reference/parserES5SymbolProperty1.errors.txt b/tests/baselines/reference/parserES5SymbolProperty1.errors.txt
index 1d7d361ef3a15..ee60b2c9eeb1f 100644
--- a/tests/baselines/reference/parserES5SymbolProperty1.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty1.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty1.ts(2,5): error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty1.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty1.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty1.ts (2 errors) ====
     interface I {
         [Symbol.iterator]: string;
+        ~~~~~~~~~~~~~~~~~
+!!! error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty2.errors.txt b/tests/baselines/reference/parserES5SymbolProperty2.errors.txt
index 581f65b0a499b..48d36c7ca1764 100644
--- a/tests/baselines/reference/parserES5SymbolProperty2.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty2.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty2.ts(2,5): error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty2.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty2.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty2.ts (2 errors) ====
     interface I {
         [Symbol.unscopables](): string;
+        ~~~~~~~~~~~~~~~~~~~~
+!!! error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty3.errors.txt b/tests/baselines/reference/parserES5SymbolProperty3.errors.txt
index 8db74c5125574..e1e5dc9638caf 100644
--- a/tests/baselines/reference/parserES5SymbolProperty3.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty3.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty3.ts(2,5): error TS1165: A computed property name in an ambient context must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty3.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty3.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty3.ts (2 errors) ====
     declare class C {
         [Symbol.unscopables](): string;
+        ~~~~~~~~~~~~~~~~~~~~
+!!! error TS1165: A computed property name in an ambient context must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty4.errors.txt b/tests/baselines/reference/parserES5SymbolProperty4.errors.txt
index 1fd929502e3a6..11c3d57381319 100644
--- a/tests/baselines/reference/parserES5SymbolProperty4.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty4.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty4.ts(2,5): error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty4.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty4.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty4.ts (2 errors) ====
     declare class C {
         [Symbol.isRegExp]: string;
+        ~~~~~~~~~~~~~~~~~
+!!! error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty5.errors.txt b/tests/baselines/reference/parserES5SymbolProperty5.errors.txt
index a4b25f4b64dd2..16218ec88e5a6 100644
--- a/tests/baselines/reference/parserES5SymbolProperty5.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty5.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty5.ts(2,5): error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty5.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty5.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty5.ts (2 errors) ====
     class C {
         [Symbol.isRegExp]: string;
+        ~~~~~~~~~~~~~~~~~
+!!! error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty5.js b/tests/baselines/reference/parserES5SymbolProperty5.js
index 9042b73bbd98e..bd4eb997f5a21 100644
--- a/tests/baselines/reference/parserES5SymbolProperty5.js
+++ b/tests/baselines/reference/parserES5SymbolProperty5.js
@@ -9,3 +9,4 @@ var C = /** @class */ (function () {
     }
     return C;
 }());
+Symbol.isRegExp;
diff --git a/tests/baselines/reference/parserES5SymbolProperty6.errors.txt b/tests/baselines/reference/parserES5SymbolProperty6.errors.txt
index 26a4d1e8efe42..e88a5e3935271 100644
--- a/tests/baselines/reference/parserES5SymbolProperty6.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty6.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty6.ts(2,5): error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty6.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty6.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty6.ts (2 errors) ====
     class C {
         [Symbol.toStringTag]: string = "";
+        ~~~~~~~~~~~~~~~~~~~~
+!!! error TS1166: A computed property name in a class property declaration must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty6.js b/tests/baselines/reference/parserES5SymbolProperty6.js
index da7c05716219e..feda26811f7d8 100644
--- a/tests/baselines/reference/parserES5SymbolProperty6.js
+++ b/tests/baselines/reference/parserES5SymbolProperty6.js
@@ -4,9 +4,11 @@ class C {
 }
 
 //// [parserES5SymbolProperty6.js]
+var _a;
 var C = /** @class */ (function () {
     function C() {
-        this[Symbol.toStringTag] = "";
+        this[_a] = "";
     }
     return C;
 }());
+_a = Symbol.toStringTag;
diff --git a/tests/baselines/reference/parserES5SymbolProperty8.errors.txt b/tests/baselines/reference/parserES5SymbolProperty8.errors.txt
index 5b4c0b99b5165..bdc626329722d 100644
--- a/tests/baselines/reference/parserES5SymbolProperty8.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty8.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty8.ts(2,5): error TS1170: A computed property name in a type literal must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty8.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty8.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty8.ts (2 errors) ====
     var x: {
         [Symbol.toPrimitive](): string
+        ~~~~~~~~~~~~~~~~~~~~
+!!! error TS1170: A computed property name in a type literal must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty8.types b/tests/baselines/reference/parserES5SymbolProperty8.types
index fcafdfd2ae280..fe070af9cedd7 100644
--- a/tests/baselines/reference/parserES5SymbolProperty8.types
+++ b/tests/baselines/reference/parserES5SymbolProperty8.types
@@ -1,6 +1,6 @@
 === tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty8.ts ===
 var x: {
->x : { [Symbol.toPrimitive](): string; }
+>x : {}
 
     [Symbol.toPrimitive](): string
 >[Symbol.toPrimitive] : () => string
diff --git a/tests/baselines/reference/parserES5SymbolProperty9.errors.txt b/tests/baselines/reference/parserES5SymbolProperty9.errors.txt
index 6ff6f65f0cd1a..79fa4b5ddf008 100644
--- a/tests/baselines/reference/parserES5SymbolProperty9.errors.txt
+++ b/tests/baselines/reference/parserES5SymbolProperty9.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty9.ts(2,5): error TS1170: A computed property name in a type literal must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty9.ts(2,6): error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
 
 
-==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty9.ts (1 errors) ====
+==== tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty9.ts (2 errors) ====
     var x: {
         [Symbol.toPrimitive]: string
+        ~~~~~~~~~~~~~~~~~~~~
+!!! error TS1170: A computed property name in a type literal must refer to an expression whose type is a literal type or a 'unique symbol' type.
          ~~~~~~
 !!! error TS2693: 'Symbol' only refers to a type, but is being used as a value here.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/parserES5SymbolProperty9.types b/tests/baselines/reference/parserES5SymbolProperty9.types
index b5568a201a597..b4d47ffc3f3ed 100644
--- a/tests/baselines/reference/parserES5SymbolProperty9.types
+++ b/tests/baselines/reference/parserES5SymbolProperty9.types
@@ -1,6 +1,6 @@
 === tests/cases/conformance/parser/ecmascript5/Symbols/parserES5SymbolProperty9.ts ===
 var x: {
->x : { [Symbol.toPrimitive]: string; }
+>x : {}
 
     [Symbol.toPrimitive]: string
 >[Symbol.toPrimitive] : string
diff --git a/tests/baselines/reference/parserSymbolIndexer5.types b/tests/baselines/reference/parserSymbolIndexer5.types
index e7a51c52393d3..864312e54389f 100644
--- a/tests/baselines/reference/parserSymbolIndexer5.types
+++ b/tests/baselines/reference/parserSymbolIndexer5.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/parser/ecmascript6/Symbols/parserSymbolIndexer5.ts ===
 var x = {
->x : { [x: number]: any; "": any; }
->{    [s: symbol]: ""} : { [x: number]: any; "": any; }
+>x : { [x: string]: any; "": any; }
+>{    [s: symbol]: ""} : { [x: string]: any; "": any; }
 
     [s: symbol]: ""
 >[s : any
diff --git a/tests/baselines/reference/parserSymbolProperty1.types b/tests/baselines/reference/parserSymbolProperty1.types
index 29ea682a2bd93..fb4196f96463f 100644
--- a/tests/baselines/reference/parserSymbolProperty1.types
+++ b/tests/baselines/reference/parserSymbolProperty1.types
@@ -4,7 +4,7 @@ interface I {
 
     [Symbol.iterator]: string;
 >[Symbol.iterator] : string
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty2.types b/tests/baselines/reference/parserSymbolProperty2.types
index e6f207ec76693..a4a2f2e55de8c 100644
--- a/tests/baselines/reference/parserSymbolProperty2.types
+++ b/tests/baselines/reference/parserSymbolProperty2.types
@@ -4,7 +4,7 @@ interface I {
 
     [Symbol.unscopables](): string;
 >[Symbol.unscopables] : () => string
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty3.types b/tests/baselines/reference/parserSymbolProperty3.types
index 342b8f979b6aa..95264a2932656 100644
--- a/tests/baselines/reference/parserSymbolProperty3.types
+++ b/tests/baselines/reference/parserSymbolProperty3.types
@@ -4,7 +4,7 @@ declare class C {
 
     [Symbol.unscopables](): string;
 >[Symbol.unscopables] : () => string
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty4.types b/tests/baselines/reference/parserSymbolProperty4.types
index d59c507d1d202..bc0d67e056e19 100644
--- a/tests/baselines/reference/parserSymbolProperty4.types
+++ b/tests/baselines/reference/parserSymbolProperty4.types
@@ -4,7 +4,7 @@ declare class C {
 
     [Symbol.toPrimitive]: string;
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty5.js b/tests/baselines/reference/parserSymbolProperty5.js
index 62a805602d1b1..2a3a558eeeed9 100644
--- a/tests/baselines/reference/parserSymbolProperty5.js
+++ b/tests/baselines/reference/parserSymbolProperty5.js
@@ -6,3 +6,4 @@ class C {
 //// [parserSymbolProperty5.js]
 class C {
 }
+Symbol.toPrimitive;
diff --git a/tests/baselines/reference/parserSymbolProperty5.types b/tests/baselines/reference/parserSymbolProperty5.types
index 0c07379a4ebbd..e6941ab3c7732 100644
--- a/tests/baselines/reference/parserSymbolProperty5.types
+++ b/tests/baselines/reference/parserSymbolProperty5.types
@@ -4,7 +4,7 @@ class C {
 
     [Symbol.toPrimitive]: string;
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty6.js b/tests/baselines/reference/parserSymbolProperty6.js
index d2aa55fe0859a..4bb5a7c01f41b 100644
--- a/tests/baselines/reference/parserSymbolProperty6.js
+++ b/tests/baselines/reference/parserSymbolProperty6.js
@@ -4,8 +4,10 @@ class C {
 }
 
 //// [parserSymbolProperty6.js]
+var _a;
 class C {
     constructor() {
-        this[Symbol.toStringTag] = "";
+        this[_a] = "";
     }
 }
+_a = Symbol.toStringTag;
diff --git a/tests/baselines/reference/parserSymbolProperty6.types b/tests/baselines/reference/parserSymbolProperty6.types
index fb2003b9db942..f9e1f3e979fdb 100644
--- a/tests/baselines/reference/parserSymbolProperty6.types
+++ b/tests/baselines/reference/parserSymbolProperty6.types
@@ -4,8 +4,8 @@ class C {
 
     [Symbol.toStringTag]: string = "";
 >[Symbol.toStringTag] : string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >"" : ""
 }
diff --git a/tests/baselines/reference/parserSymbolProperty7.types b/tests/baselines/reference/parserSymbolProperty7.types
index 9ac1ca2f7d32f..18e5a95aa2c27 100644
--- a/tests/baselines/reference/parserSymbolProperty7.types
+++ b/tests/baselines/reference/parserSymbolProperty7.types
@@ -4,7 +4,7 @@ class C {
 
     [Symbol.toStringTag](): void { }
 >[Symbol.toStringTag] : () => void
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty8.types b/tests/baselines/reference/parserSymbolProperty8.types
index dfac56694359a..29cea864c62fe 100644
--- a/tests/baselines/reference/parserSymbolProperty8.types
+++ b/tests/baselines/reference/parserSymbolProperty8.types
@@ -4,7 +4,7 @@ var x: {
 
     [Symbol.toPrimitive](): string
 >[Symbol.toPrimitive] : () => string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/parserSymbolProperty9.types b/tests/baselines/reference/parserSymbolProperty9.types
index 48d3f56a2f3fe..a2a96591b60b4 100644
--- a/tests/baselines/reference/parserSymbolProperty9.types
+++ b/tests/baselines/reference/parserSymbolProperty9.types
@@ -4,7 +4,7 @@ var x: {
 
     [Symbol.toPrimitive]: string
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/privateIndexer2.types b/tests/baselines/reference/privateIndexer2.types
index fcfabc3f799c0..216360cac5e98 100644
--- a/tests/baselines/reference/privateIndexer2.types
+++ b/tests/baselines/reference/privateIndexer2.types
@@ -3,7 +3,7 @@
 
 var x = {
 >x : any
->{    private [x: string]: string;} : { [x: number]: any; string: any; }
+>{    private [x: string]: string;} : { [x: string]: any; string: any; }
 
     private [x: string]: string;
 >[x : any
diff --git a/tests/baselines/reference/superSymbolIndexedAccess2.types b/tests/baselines/reference/superSymbolIndexedAccess2.types
index f76c768444066..de4dac377f813 100644
--- a/tests/baselines/reference/superSymbolIndexedAccess2.types
+++ b/tests/baselines/reference/superSymbolIndexedAccess2.types
@@ -4,9 +4,9 @@ class Foo {
 
     [Symbol.isConcatSpreadable]() {
 >[Symbol.isConcatSpreadable] : () => number
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
         return 0;
 >0 : 0
@@ -19,16 +19,16 @@ class Bar extends Foo {
 
     [Symbol.isConcatSpreadable]() {
 >[Symbol.isConcatSpreadable] : () => number
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
         return super[Symbol.isConcatSpreadable]();
 >super[Symbol.isConcatSpreadable]() : number
 >super[Symbol.isConcatSpreadable] : () => number
 >super : Foo
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
     }
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit1.js b/tests/baselines/reference/symbolDeclarationEmit1.js
index b8ca5495ba759..e2904372a104a 100644
--- a/tests/baselines/reference/symbolDeclarationEmit1.js
+++ b/tests/baselines/reference/symbolDeclarationEmit1.js
@@ -6,6 +6,7 @@ class C {
 //// [symbolDeclarationEmit1.js]
 class C {
 }
+Symbol.toPrimitive;
 
 
 //// [symbolDeclarationEmit1.d.ts]
diff --git a/tests/baselines/reference/symbolDeclarationEmit1.types b/tests/baselines/reference/symbolDeclarationEmit1.types
index 0493f5b327274..533f2607167d1 100644
--- a/tests/baselines/reference/symbolDeclarationEmit1.types
+++ b/tests/baselines/reference/symbolDeclarationEmit1.types
@@ -4,7 +4,7 @@ class C {
 
     [Symbol.toPrimitive]: number;
 >[Symbol.toPrimitive] : number
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit10.types b/tests/baselines/reference/symbolDeclarationEmit10.types
index 9a47c89173979..4492dba079c92 100644
--- a/tests/baselines/reference/symbolDeclarationEmit10.types
+++ b/tests/baselines/reference/symbolDeclarationEmit10.types
@@ -5,15 +5,15 @@ var obj = {
 
     get [Symbol.isConcatSpreadable]() { return '' },
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >'' : ""
 
     set [Symbol.isConcatSpreadable](x) { }
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >x : string
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit11.js b/tests/baselines/reference/symbolDeclarationEmit11.js
index 25af4c4306475..06c99f96d3ead 100644
--- a/tests/baselines/reference/symbolDeclarationEmit11.js
+++ b/tests/baselines/reference/symbolDeclarationEmit11.js
@@ -7,12 +7,13 @@ class C {
 }
 
 //// [symbolDeclarationEmit11.js]
+var _a;
 class C {
-    static [Symbol.isConcatSpreadable]() { }
+    static [(_a = Symbol.iterator, Symbol.isConcatSpreadable)]() { }
     static get [Symbol.toPrimitive]() { return ""; }
     static set [Symbol.toPrimitive](x) { }
 }
-C[Symbol.iterator] = 0;
+C[_a] = 0;
 
 
 //// [symbolDeclarationEmit11.d.ts]
diff --git a/tests/baselines/reference/symbolDeclarationEmit11.types b/tests/baselines/reference/symbolDeclarationEmit11.types
index 2d9c9a95e0861..9bb3176e99505 100644
--- a/tests/baselines/reference/symbolDeclarationEmit11.types
+++ b/tests/baselines/reference/symbolDeclarationEmit11.types
@@ -4,28 +4,28 @@ class C {
 
     static [Symbol.iterator] = 0;
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
     static [Symbol.isConcatSpreadable]() { }
 >[Symbol.isConcatSpreadable] : () => void
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     static get [Symbol.toPrimitive]() { return ""; }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >"" : ""
 
     static set [Symbol.toPrimitive](x) { }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : string
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit12.errors.txt b/tests/baselines/reference/symbolDeclarationEmit12.errors.txt
index d9759c00f6de2..b2e83d92adf04 100644
--- a/tests/baselines/reference/symbolDeclarationEmit12.errors.txt
+++ b/tests/baselines/reference/symbolDeclarationEmit12.errors.txt
@@ -1,6 +1,6 @@
-tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(5,9): error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
-tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(9,13): error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
-tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(10,13): error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
+tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(5,9): error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
+tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(9,13): error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
+tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(10,13): error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
 
 
 ==== tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts (3 errors) ====
@@ -10,15 +10,15 @@ tests/cases/conformance/es6/Symbols/symbolDeclarationEmit12.ts(10,13): error TS2
             [Symbol.iterator]: I;
             [Symbol.toPrimitive](x: I) { }
             ~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
+!!! error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
             [Symbol.isConcatSpreadable](): I {
                 return undefined
             }
             get [Symbol.toPrimitive]() { return undefined; }
                 ~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
+!!! error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
             set [Symbol.toPrimitive](x: I) { }
                 ~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.toPrimitive]'.
+!!! error TS2718: Duplicate declaration '[Symbol.toPrimitive]'.
         }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolDeclarationEmit12.js b/tests/baselines/reference/symbolDeclarationEmit12.js
index d700f9ac51092..2771037b2f142 100644
--- a/tests/baselines/reference/symbolDeclarationEmit12.js
+++ b/tests/baselines/reference/symbolDeclarationEmit12.js
@@ -16,7 +16,7 @@ module M {
 var M;
 (function (M) {
     class C {
-        [Symbol.toPrimitive](x) { }
+        [(Symbol.iterator, Symbol.toPrimitive)](x) { }
         [Symbol.isConcatSpreadable]() {
             return undefined;
         }
diff --git a/tests/baselines/reference/symbolDeclarationEmit12.types b/tests/baselines/reference/symbolDeclarationEmit12.types
index 71a66861f9ae6..121b66feba81a 100644
--- a/tests/baselines/reference/symbolDeclarationEmit12.types
+++ b/tests/baselines/reference/symbolDeclarationEmit12.types
@@ -10,24 +10,24 @@ module M {
 
         [Symbol.iterator]: I;
 >[Symbol.iterator] : I
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >I : I
 
         [Symbol.toPrimitive](x: I) { }
 >[Symbol.toPrimitive] : (x: I) => void
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : I
 >I : I
 
         [Symbol.isConcatSpreadable](): I {
 >[Symbol.isConcatSpreadable] : () => I
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >I : I
 
             return undefined
@@ -35,16 +35,16 @@ module M {
         }
         get [Symbol.toPrimitive]() { return undefined; }
 >[Symbol.toPrimitive] : any
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >undefined : undefined
 
         set [Symbol.toPrimitive](x: I) { }
 >[Symbol.toPrimitive] : I
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : I
 >I : I
     }
diff --git a/tests/baselines/reference/symbolDeclarationEmit13.types b/tests/baselines/reference/symbolDeclarationEmit13.types
index 26e2087c2e9c4..9ffb1d8fbf18e 100644
--- a/tests/baselines/reference/symbolDeclarationEmit13.types
+++ b/tests/baselines/reference/symbolDeclarationEmit13.types
@@ -4,15 +4,15 @@ class C {
 
     get [Symbol.toPrimitive]() { return ""; }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >"" : ""
 
     set [Symbol.toStringTag](x) { }
 >[Symbol.toStringTag] : any
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >x : any
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit14.types b/tests/baselines/reference/symbolDeclarationEmit14.types
index e8e2490e9fe96..daf81242ecb46 100644
--- a/tests/baselines/reference/symbolDeclarationEmit14.types
+++ b/tests/baselines/reference/symbolDeclarationEmit14.types
@@ -4,15 +4,15 @@ class C {
 
     get [Symbol.toPrimitive]() { return ""; }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >"" : ""
 
     get [Symbol.toStringTag]() { return ""; }
 >[Symbol.toStringTag] : string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >"" : ""
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit2.js b/tests/baselines/reference/symbolDeclarationEmit2.js
index 3fde1f6b46762..ae649b3d62afd 100644
--- a/tests/baselines/reference/symbolDeclarationEmit2.js
+++ b/tests/baselines/reference/symbolDeclarationEmit2.js
@@ -4,11 +4,13 @@ class C {
 }
 
 //// [symbolDeclarationEmit2.js]
+var _a;
 class C {
     constructor() {
-        this[Symbol.toPrimitive] = "";
+        this[_a] = "";
     }
 }
+_a = Symbol.toPrimitive;
 
 
 //// [symbolDeclarationEmit2.d.ts]
diff --git a/tests/baselines/reference/symbolDeclarationEmit2.types b/tests/baselines/reference/symbolDeclarationEmit2.types
index e12781ad742f6..1796f23fa064c 100644
--- a/tests/baselines/reference/symbolDeclarationEmit2.types
+++ b/tests/baselines/reference/symbolDeclarationEmit2.types
@@ -4,8 +4,8 @@ class C {
 
     [Symbol.toPrimitive] = "";
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >"" : ""
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit3.types b/tests/baselines/reference/symbolDeclarationEmit3.types
index 7166bc3fa931b..3b8e37f5188e0 100644
--- a/tests/baselines/reference/symbolDeclarationEmit3.types
+++ b/tests/baselines/reference/symbolDeclarationEmit3.types
@@ -4,22 +4,22 @@ class C {
 
     [Symbol.toPrimitive](x: number);
 >[Symbol.toPrimitive] : { (x: number): any; (x: string): any; }
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : number
 
     [Symbol.toPrimitive](x: string);
 >[Symbol.toPrimitive] : { (x: number): any; (x: string): any; }
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : string
 
     [Symbol.toPrimitive](x: any) { }
 >[Symbol.toPrimitive] : { (x: number): any; (x: string): any; }
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : any
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit4.types b/tests/baselines/reference/symbolDeclarationEmit4.types
index e73791f6901ab..347ac0943de63 100644
--- a/tests/baselines/reference/symbolDeclarationEmit4.types
+++ b/tests/baselines/reference/symbolDeclarationEmit4.types
@@ -4,15 +4,15 @@ class C {
 
     get [Symbol.toPrimitive]() { return ""; }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >"" : ""
 
     set [Symbol.toPrimitive](x) { }
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >x : string
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit5.types b/tests/baselines/reference/symbolDeclarationEmit5.types
index 75fc6dc6a7547..9d50203115db3 100644
--- a/tests/baselines/reference/symbolDeclarationEmit5.types
+++ b/tests/baselines/reference/symbolDeclarationEmit5.types
@@ -4,7 +4,7 @@ interface I {
 
     [Symbol.isConcatSpreadable](): string;
 >[Symbol.isConcatSpreadable] : () => string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit6.types b/tests/baselines/reference/symbolDeclarationEmit6.types
index 1a22dd3278bb6..857bb7dfef278 100644
--- a/tests/baselines/reference/symbolDeclarationEmit6.types
+++ b/tests/baselines/reference/symbolDeclarationEmit6.types
@@ -4,7 +4,7 @@ interface I {
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit7.types b/tests/baselines/reference/symbolDeclarationEmit7.types
index 207d3f0bab052..2166dfd46788c 100644
--- a/tests/baselines/reference/symbolDeclarationEmit7.types
+++ b/tests/baselines/reference/symbolDeclarationEmit7.types
@@ -4,7 +4,7 @@ var obj: {
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit8.types b/tests/baselines/reference/symbolDeclarationEmit8.types
index bf8309e4cdede..98dbc63529681 100644
--- a/tests/baselines/reference/symbolDeclarationEmit8.types
+++ b/tests/baselines/reference/symbolDeclarationEmit8.types
@@ -5,8 +5,8 @@ var obj = {
 
     [Symbol.isConcatSpreadable]: 0
 >[Symbol.isConcatSpreadable] : number
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >0 : 0
 }
diff --git a/tests/baselines/reference/symbolDeclarationEmit9.types b/tests/baselines/reference/symbolDeclarationEmit9.types
index 176009d28c9f5..532abeb103663 100644
--- a/tests/baselines/reference/symbolDeclarationEmit9.types
+++ b/tests/baselines/reference/symbolDeclarationEmit9.types
@@ -5,7 +5,7 @@ var obj = {
 
     [Symbol.isConcatSpreadable]() { }
 >[Symbol.isConcatSpreadable] : () => void
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolProperty10.js b/tests/baselines/reference/symbolProperty10.js
index 74bcf886461e5..7e4d14c1622e3 100644
--- a/tests/baselines/reference/symbolProperty10.js
+++ b/tests/baselines/reference/symbolProperty10.js
@@ -13,6 +13,7 @@ var c: C = i;
 //// [symbolProperty10.js]
 class C {
 }
+Symbol.iterator;
 var i;
 i = new C;
 var c = i;
diff --git a/tests/baselines/reference/symbolProperty10.types b/tests/baselines/reference/symbolProperty10.types
index bcc642e936f74..eb38c4af0d784 100644
--- a/tests/baselines/reference/symbolProperty10.types
+++ b/tests/baselines/reference/symbolProperty10.types
@@ -4,9 +4,9 @@ class C {
 
     [Symbol.iterator]: { x; y };
 >[Symbol.iterator] : { x: any; y: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 >y : any
 }
@@ -15,9 +15,9 @@ interface I {
 
     [Symbol.iterator]?: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty11.types b/tests/baselines/reference/symbolProperty11.types
index acf95b8315f42..592e5a982a61c 100644
--- a/tests/baselines/reference/symbolProperty11.types
+++ b/tests/baselines/reference/symbolProperty11.types
@@ -7,9 +7,9 @@ interface I {
 
     [Symbol.iterator]?: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty12.js b/tests/baselines/reference/symbolProperty12.js
index 474ec4a0ffad8..b59633f3314a8 100644
--- a/tests/baselines/reference/symbolProperty12.js
+++ b/tests/baselines/reference/symbolProperty12.js
@@ -13,6 +13,7 @@ var c: C = i;
 //// [symbolProperty12.js]
 class C {
 }
+Symbol.iterator;
 var i;
 i = new C;
 var c = i;
diff --git a/tests/baselines/reference/symbolProperty12.types b/tests/baselines/reference/symbolProperty12.types
index 16b0313d0e482..471611518df73 100644
--- a/tests/baselines/reference/symbolProperty12.types
+++ b/tests/baselines/reference/symbolProperty12.types
@@ -4,9 +4,9 @@ class C {
 
     private [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 interface I {
@@ -14,9 +14,9 @@ interface I {
 
     [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty13.js b/tests/baselines/reference/symbolProperty13.js
index d7620d01159dc..4b44317b27f4f 100644
--- a/tests/baselines/reference/symbolProperty13.js
+++ b/tests/baselines/reference/symbolProperty13.js
@@ -19,6 +19,7 @@ bar(i);
 //// [symbolProperty13.js]
 class C {
 }
+Symbol.iterator;
 foo(new C);
 var i;
 bar(i);
diff --git a/tests/baselines/reference/symbolProperty13.types b/tests/baselines/reference/symbolProperty13.types
index adce2ae7cb0d4..5013af247661b 100644
--- a/tests/baselines/reference/symbolProperty13.types
+++ b/tests/baselines/reference/symbolProperty13.types
@@ -4,9 +4,9 @@ class C {
 
     [Symbol.iterator]: { x; y };
 >[Symbol.iterator] : { x: any; y: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 >y : any
 }
@@ -15,9 +15,9 @@ interface I {
 
     [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty14.js b/tests/baselines/reference/symbolProperty14.js
index 716bc68b43029..5244aebfc4b16 100644
--- a/tests/baselines/reference/symbolProperty14.js
+++ b/tests/baselines/reference/symbolProperty14.js
@@ -19,6 +19,7 @@ bar(i);
 //// [symbolProperty14.js]
 class C {
 }
+Symbol.iterator;
 foo(new C);
 var i;
 bar(i);
diff --git a/tests/baselines/reference/symbolProperty14.types b/tests/baselines/reference/symbolProperty14.types
index 2cc344444ce29..cb4dbdb34b6f0 100644
--- a/tests/baselines/reference/symbolProperty14.types
+++ b/tests/baselines/reference/symbolProperty14.types
@@ -4,9 +4,9 @@ class C {
 
     [Symbol.iterator]: { x; y };
 >[Symbol.iterator] : { x: any; y: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 >y : any
 }
@@ -15,9 +15,9 @@ interface I {
 
     [Symbol.iterator]?: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty15.types b/tests/baselines/reference/symbolProperty15.types
index 8403aaf60128f..437f970a6e25f 100644
--- a/tests/baselines/reference/symbolProperty15.types
+++ b/tests/baselines/reference/symbolProperty15.types
@@ -7,9 +7,9 @@ interface I {
 
     [Symbol.iterator]?: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty16.js b/tests/baselines/reference/symbolProperty16.js
index 1382d913104f9..54e826db86cf3 100644
--- a/tests/baselines/reference/symbolProperty16.js
+++ b/tests/baselines/reference/symbolProperty16.js
@@ -19,6 +19,7 @@ bar(i);
 //// [symbolProperty16.js]
 class C {
 }
+Symbol.iterator;
 foo(new C);
 var i;
 bar(i);
diff --git a/tests/baselines/reference/symbolProperty16.types b/tests/baselines/reference/symbolProperty16.types
index e276fad08e4ed..506525774c852 100644
--- a/tests/baselines/reference/symbolProperty16.types
+++ b/tests/baselines/reference/symbolProperty16.types
@@ -4,9 +4,9 @@ class C {
 
     private [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 interface I {
@@ -14,9 +14,9 @@ interface I {
 
     [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolProperty17.types b/tests/baselines/reference/symbolProperty17.types
index d71fe919becc6..9374b49e3af0a 100644
--- a/tests/baselines/reference/symbolProperty17.types
+++ b/tests/baselines/reference/symbolProperty17.types
@@ -4,9 +4,9 @@ interface I {
 
     [Symbol.iterator]: number;
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
     [s: symbol]: string;
 >s : symbol
@@ -23,7 +23,7 @@ var it = i[Symbol.iterator];
 >it : number
 >i[Symbol.iterator] : number
 >i : I
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
diff --git a/tests/baselines/reference/symbolProperty18.types b/tests/baselines/reference/symbolProperty18.types
index 4a4d9e413ae5e..520ce8e96bed3 100644
--- a/tests/baselines/reference/symbolProperty18.types
+++ b/tests/baselines/reference/symbolProperty18.types
@@ -5,23 +5,23 @@ var i = {
 
     [Symbol.iterator]: 0,
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
     [Symbol.toStringTag]() { return "" },
 >[Symbol.toStringTag] : () => string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >"" : ""
 
     set [Symbol.toPrimitive](p: boolean) { }
 >[Symbol.toPrimitive] : boolean
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >p : boolean
 }
 
@@ -29,25 +29,25 @@ var it = i[Symbol.iterator];
 >it : number
 >i[Symbol.iterator] : number
 >i : { [Symbol.iterator]: number; [Symbol.toStringTag](): string; [Symbol.toPrimitive]: boolean; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
 var str = i[Symbol.toStringTag]();
 >str : string
 >i[Symbol.toStringTag]() : string
 >i[Symbol.toStringTag] : () => string
 >i : { [Symbol.iterator]: number; [Symbol.toStringTag](): string; [Symbol.toPrimitive]: boolean; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
 i[Symbol.toPrimitive] = false;
 >i[Symbol.toPrimitive] = false : false
 >i[Symbol.toPrimitive] : boolean
 >i : { [Symbol.iterator]: number; [Symbol.toStringTag](): string; [Symbol.toPrimitive]: boolean; }
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >false : false
 
diff --git a/tests/baselines/reference/symbolProperty19.types b/tests/baselines/reference/symbolProperty19.types
index 8d369de58c2d0..5483416f24003 100644
--- a/tests/baselines/reference/symbolProperty19.types
+++ b/tests/baselines/reference/symbolProperty19.types
@@ -5,18 +5,18 @@ var i = {
 
     [Symbol.iterator]: { p: null },
 >[Symbol.iterator] : { p: null; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >{ p: null } : { p: null; }
 >p : null
 >null : null
 
     [Symbol.toStringTag]() { return { p: undefined }; }
 >[Symbol.toStringTag] : () => { p: any; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >{ p: undefined } : { p: undefined; }
 >p : undefined
 >undefined : undefined
@@ -26,16 +26,16 @@ var it = i[Symbol.iterator];
 >it : { p: any; }
 >i[Symbol.iterator] : { p: any; }
 >i : { [Symbol.iterator]: { p: any; }; [Symbol.toStringTag](): { p: any; }; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
 var str = i[Symbol.toStringTag]();
 >str : { p: any; }
 >i[Symbol.toStringTag]() : { p: any; }
 >i[Symbol.toStringTag] : () => { p: any; }
 >i : { [Symbol.iterator]: { p: any; }; [Symbol.toStringTag](): { p: any; }; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
diff --git a/tests/baselines/reference/symbolProperty20.types b/tests/baselines/reference/symbolProperty20.types
index 4489197c9f635..805020ee9f010 100644
--- a/tests/baselines/reference/symbolProperty20.types
+++ b/tests/baselines/reference/symbolProperty20.types
@@ -4,16 +4,16 @@ interface I {
 
     [Symbol.iterator]: (s: string) => string;
 >[Symbol.iterator] : (s: string) => string
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >s : string
 
     [Symbol.toStringTag](s: number): number;
 >[Symbol.toStringTag] : (s: number) => number
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >s : number
 }
 
@@ -24,18 +24,18 @@ var i: I = {
 
     [Symbol.iterator]: s => s,
 >[Symbol.iterator] : (s: string) => string
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >s => s : (s: string) => string
 >s : string
 >s : string
 
     [Symbol.toStringTag](n) { return n; }
 >[Symbol.toStringTag] : (n: number) => number
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >n : number
 >n : number
 }
diff --git a/tests/baselines/reference/symbolProperty21.types b/tests/baselines/reference/symbolProperty21.types
index 9141cffbb22de..afec8a9c8b8b4 100644
--- a/tests/baselines/reference/symbolProperty21.types
+++ b/tests/baselines/reference/symbolProperty21.types
@@ -6,16 +6,16 @@ interface I<T, U> {
 
     [Symbol.unscopables]: T;
 >[Symbol.unscopables] : T
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 >T : T
 
     [Symbol.isConcatSpreadable]: U;
 >[Symbol.isConcatSpreadable] : U
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >U : U
 }
 
@@ -39,23 +39,23 @@ foo({
 
     [Symbol.isConcatSpreadable]: "",
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >"" : ""
 
     [Symbol.toPrimitive]: 0,
 >[Symbol.toPrimitive] : number
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 >0 : 0
 
     [Symbol.unscopables]: true
 >[Symbol.unscopables] : boolean
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 >true : true
 
 });
diff --git a/tests/baselines/reference/symbolProperty22.types b/tests/baselines/reference/symbolProperty22.types
index 478fb6c2c2eb1..11a9839ce669b 100644
--- a/tests/baselines/reference/symbolProperty22.types
+++ b/tests/baselines/reference/symbolProperty22.types
@@ -6,9 +6,9 @@ interface I<T, U> {
 
     [Symbol.unscopables](x: T): U;
 >[Symbol.unscopables] : (x: T) => U
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 >x : T
 >T : T
 >U : U
@@ -32,9 +32,9 @@ foo("", { [Symbol.unscopables]: s => s.length });
 >"" : ""
 >{ [Symbol.unscopables]: s => s.length } : { [Symbol.unscopables]: (s: string) => number; }
 >[Symbol.unscopables] : (s: string) => number
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 >s => s.length : (s: string) => number
 >s : string
 >s.length : number
diff --git a/tests/baselines/reference/symbolProperty23.types b/tests/baselines/reference/symbolProperty23.types
index 02df66e6c7805..caf96ba6893f4 100644
--- a/tests/baselines/reference/symbolProperty23.types
+++ b/tests/baselines/reference/symbolProperty23.types
@@ -4,9 +4,9 @@ interface I {
 
     [Symbol.toPrimitive]: () => boolean;
 >[Symbol.toPrimitive] : () => boolean
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
 
 class C implements I {
@@ -15,9 +15,9 @@ class C implements I {
 
     [Symbol.toPrimitive]() {
 >[Symbol.toPrimitive] : () => boolean
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
         return true;
 >true : true
diff --git a/tests/baselines/reference/symbolProperty24.types b/tests/baselines/reference/symbolProperty24.types
index f1de8a95632bc..5706bd983893d 100644
--- a/tests/baselines/reference/symbolProperty24.types
+++ b/tests/baselines/reference/symbolProperty24.types
@@ -4,9 +4,9 @@ interface I {
 
     [Symbol.toPrimitive]: () => boolean;
 >[Symbol.toPrimitive] : () => boolean
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
 
 class C implements I {
@@ -15,9 +15,9 @@ class C implements I {
 
     [Symbol.toPrimitive]() {
 >[Symbol.toPrimitive] : () => string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty25.types b/tests/baselines/reference/symbolProperty25.types
index 41be32c876f02..f4dd72e9ad8f9 100644
--- a/tests/baselines/reference/symbolProperty25.types
+++ b/tests/baselines/reference/symbolProperty25.types
@@ -4,9 +4,9 @@ interface I {
 
     [Symbol.toPrimitive]: () => boolean;
 >[Symbol.toPrimitive] : () => boolean
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
 
 class C implements I {
@@ -15,9 +15,9 @@ class C implements I {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty26.types b/tests/baselines/reference/symbolProperty26.types
index abea57bd6903e..a79626467899c 100644
--- a/tests/baselines/reference/symbolProperty26.types
+++ b/tests/baselines/reference/symbolProperty26.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return "";
 >"" : ""
@@ -19,9 +19,9 @@ class C2 extends C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty27.types b/tests/baselines/reference/symbolProperty27.types
index b27ffdff71339..98ae6c0784e81 100644
--- a/tests/baselines/reference/symbolProperty27.types
+++ b/tests/baselines/reference/symbolProperty27.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => {}
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return {};
 >{} : {}
@@ -19,9 +19,9 @@ class C2 extends C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty28.types b/tests/baselines/reference/symbolProperty28.types
index f1224f677cb09..fb38eadefe7e7 100644
--- a/tests/baselines/reference/symbolProperty28.types
+++ b/tests/baselines/reference/symbolProperty28.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
@@ -29,8 +29,8 @@ var obj = c[Symbol.toStringTag]().x;
 >c[Symbol.toStringTag]() : { x: string; }
 >c[Symbol.toStringTag] : () => { x: string; }
 >c : C2
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >x : string
 
diff --git a/tests/baselines/reference/symbolProperty29.types b/tests/baselines/reference/symbolProperty29.types
index f4388acb041b2..e4c5bec1e7943 100644
--- a/tests/baselines/reference/symbolProperty29.types
+++ b/tests/baselines/reference/symbolProperty29.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty30.types b/tests/baselines/reference/symbolProperty30.types
index 6d66de0fc8a28..5464ea908e7f9 100644
--- a/tests/baselines/reference/symbolProperty30.types
+++ b/tests/baselines/reference/symbolProperty30.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty31.types b/tests/baselines/reference/symbolProperty31.types
index 82c4df523c478..f1e6b72793e74 100644
--- a/tests/baselines/reference/symbolProperty31.types
+++ b/tests/baselines/reference/symbolProperty31.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty32.types b/tests/baselines/reference/symbolProperty32.types
index bf899308c0ac3..2db3c1092f077 100644
--- a/tests/baselines/reference/symbolProperty32.types
+++ b/tests/baselines/reference/symbolProperty32.types
@@ -4,9 +4,9 @@ class C1 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty33.types b/tests/baselines/reference/symbolProperty33.types
index b8ae732ca17bf..6f85c4f06d15e 100644
--- a/tests/baselines/reference/symbolProperty33.types
+++ b/tests/baselines/reference/symbolProperty33.types
@@ -5,9 +5,9 @@ class C1 extends C2 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty34.types b/tests/baselines/reference/symbolProperty34.types
index 724c676f26c68..de0b7268abd71 100644
--- a/tests/baselines/reference/symbolProperty34.types
+++ b/tests/baselines/reference/symbolProperty34.types
@@ -5,9 +5,9 @@ class C1 extends C2 {
 
     [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return { x: "" };
 >{ x: "" } : { x: string; }
diff --git a/tests/baselines/reference/symbolProperty35.types b/tests/baselines/reference/symbolProperty35.types
index 22d85c2cb203b..21758c76cd7f7 100644
--- a/tests/baselines/reference/symbolProperty35.types
+++ b/tests/baselines/reference/symbolProperty35.types
@@ -4,9 +4,9 @@ interface I1 {
 
     [Symbol.toStringTag](): { x: string }
 >[Symbol.toStringTag] : () => { x: string; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >x : string
 }
 interface I2 {
@@ -14,9 +14,9 @@ interface I2 {
 
     [Symbol.toStringTag](): { x: number }
 >[Symbol.toStringTag] : () => { x: number; }
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 >x : number
 }
 
diff --git a/tests/baselines/reference/symbolProperty36.errors.txt b/tests/baselines/reference/symbolProperty36.errors.txt
index 69102da1db387..7f0a4785c417f 100644
--- a/tests/baselines/reference/symbolProperty36.errors.txt
+++ b/tests/baselines/reference/symbolProperty36.errors.txt
@@ -1,4 +1,4 @@
-tests/cases/conformance/es6/Symbols/symbolProperty36.ts(3,5): error TS2300: Duplicate identifier '[Symbol.isConcatSpreadable]'.
+tests/cases/conformance/es6/Symbols/symbolProperty36.ts(3,5): error TS2718: Duplicate declaration '[Symbol.isConcatSpreadable]'.
 
 
 ==== tests/cases/conformance/es6/Symbols/symbolProperty36.ts (1 errors) ====
@@ -6,5 +6,5 @@ tests/cases/conformance/es6/Symbols/symbolProperty36.ts(3,5): error TS2300: Dupl
         [Symbol.isConcatSpreadable]: 0,
         [Symbol.isConcatSpreadable]: 1
         ~~~~~~~~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.isConcatSpreadable]'.
+!!! error TS2718: Duplicate declaration '[Symbol.isConcatSpreadable]'.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty36.types b/tests/baselines/reference/symbolProperty36.types
index afd80a19c9f1e..734f28f2dbb78 100644
--- a/tests/baselines/reference/symbolProperty36.types
+++ b/tests/baselines/reference/symbolProperty36.types
@@ -5,15 +5,15 @@ var x = {
 
     [Symbol.isConcatSpreadable]: 0,
 >[Symbol.isConcatSpreadable] : number
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >0 : 0
 
     [Symbol.isConcatSpreadable]: 1
 >[Symbol.isConcatSpreadable] : number
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >1 : 1
 }
diff --git a/tests/baselines/reference/symbolProperty37.types b/tests/baselines/reference/symbolProperty37.types
index 85167590ea636..38dab665164b2 100644
--- a/tests/baselines/reference/symbolProperty37.types
+++ b/tests/baselines/reference/symbolProperty37.types
@@ -4,13 +4,13 @@ interface I {
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolProperty38.types b/tests/baselines/reference/symbolProperty38.types
index bfcdbfe7bd70f..d9fca972af712 100644
--- a/tests/baselines/reference/symbolProperty38.types
+++ b/tests/baselines/reference/symbolProperty38.types
@@ -4,16 +4,16 @@ interface I {
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
 interface I {
 >I : I
 
     [Symbol.isConcatSpreadable]: string;
 >[Symbol.isConcatSpreadable] : string
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 }
diff --git a/tests/baselines/reference/symbolProperty39.types b/tests/baselines/reference/symbolProperty39.types
index 90a5fcd375e35..33461d4d1a770 100644
--- a/tests/baselines/reference/symbolProperty39.types
+++ b/tests/baselines/reference/symbolProperty39.types
@@ -4,23 +4,23 @@ class C {
 
     [Symbol.iterator](x: string): string;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : string
 
     [Symbol.iterator](x: number): number;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : number
 
     [Symbol.iterator](x: any) {
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 
         return undefined;
@@ -28,9 +28,9 @@ class C {
     }
     [Symbol.iterator](x: any) {
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 
         return undefined;
diff --git a/tests/baselines/reference/symbolProperty40.types b/tests/baselines/reference/symbolProperty40.types
index ca65adaa0bc3c..fe94507019b33 100644
--- a/tests/baselines/reference/symbolProperty40.types
+++ b/tests/baselines/reference/symbolProperty40.types
@@ -4,23 +4,23 @@ class C {
 
     [Symbol.iterator](x: string): string;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : string
 
     [Symbol.iterator](x: number): number;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : number
 
     [Symbol.iterator](x: any) {
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 
         return undefined;
@@ -37,17 +37,17 @@ c[Symbol.iterator]("");
 >c[Symbol.iterator]("") : string
 >c[Symbol.iterator] : { (x: string): string; (x: number): number; }
 >c : C
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >"" : ""
 
 c[Symbol.iterator](0);
 >c[Symbol.iterator](0) : number
 >c[Symbol.iterator] : { (x: string): string; (x: number): number; }
 >c : C
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
diff --git a/tests/baselines/reference/symbolProperty41.types b/tests/baselines/reference/symbolProperty41.types
index 76d47f90e4710..3cd7790c774b1 100644
--- a/tests/baselines/reference/symbolProperty41.types
+++ b/tests/baselines/reference/symbolProperty41.types
@@ -4,26 +4,26 @@ class C {
 
     [Symbol.iterator](x: string): { x: string };
 >[Symbol.iterator] : { (x: string): { x: string; }; (x: "hello"): { x: string; hello: string; }; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : string
 >x : string
 
     [Symbol.iterator](x: "hello"): { x: string; hello: string };
 >[Symbol.iterator] : { (x: string): { x: string; }; (x: "hello"): { x: string; hello: string; }; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : "hello"
 >x : string
 >hello : string
 
     [Symbol.iterator](x: any) {
 >[Symbol.iterator] : { (x: string): { x: string; }; (x: "hello"): { x: string; hello: string; }; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 
         return undefined;
@@ -40,17 +40,17 @@ c[Symbol.iterator]("");
 >c[Symbol.iterator]("") : { x: string; }
 >c[Symbol.iterator] : { (x: string): { x: string; }; (x: "hello"): { x: string; hello: string; }; }
 >c : C
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >"" : ""
 
 c[Symbol.iterator]("hello");
 >c[Symbol.iterator]("hello") : { x: string; hello: string; }
 >c[Symbol.iterator] : { (x: string): { x: string; }; (x: "hello"): { x: string; hello: string; }; }
 >c : C
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >"hello" : "hello"
 
diff --git a/tests/baselines/reference/symbolProperty42.types b/tests/baselines/reference/symbolProperty42.types
index 72fa0138bab31..b5ed285f12196 100644
--- a/tests/baselines/reference/symbolProperty42.types
+++ b/tests/baselines/reference/symbolProperty42.types
@@ -4,23 +4,23 @@ class C {
 
     [Symbol.iterator](x: string): string;
 >[Symbol.iterator] : { (x: string): string; (x: any): any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : string
 
     static [Symbol.iterator](x: number): number;
 >[Symbol.iterator] : (x: number) => number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : number
 
     [Symbol.iterator](x: any) {
 >[Symbol.iterator] : { (x: string): string; (x: any): any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 
         return undefined;
diff --git a/tests/baselines/reference/symbolProperty43.types b/tests/baselines/reference/symbolProperty43.types
index b4ffaeac9bd31..94ef7b692a203 100644
--- a/tests/baselines/reference/symbolProperty43.types
+++ b/tests/baselines/reference/symbolProperty43.types
@@ -4,15 +4,15 @@ class C {
 
     [Symbol.iterator](x: string): string;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : string
 
     [Symbol.iterator](x: number): number;
 >[Symbol.iterator] : { (x: string): string; (x: number): number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : number
 }
diff --git a/tests/baselines/reference/symbolProperty44.errors.txt b/tests/baselines/reference/symbolProperty44.errors.txt
index 2cef480e73664..1180383884e9a 100644
--- a/tests/baselines/reference/symbolProperty44.errors.txt
+++ b/tests/baselines/reference/symbolProperty44.errors.txt
@@ -1,17 +1,17 @@
-tests/cases/conformance/es6/Symbols/symbolProperty44.ts(2,9): error TS2300: Duplicate identifier '[Symbol.hasInstance]'.
-tests/cases/conformance/es6/Symbols/symbolProperty44.ts(5,9): error TS2300: Duplicate identifier '[Symbol.hasInstance]'.
+tests/cases/conformance/es6/Symbols/symbolProperty44.ts(2,9): error TS2718: Duplicate declaration '[Symbol.hasInstance]'.
+tests/cases/conformance/es6/Symbols/symbolProperty44.ts(5,9): error TS2718: Duplicate declaration '[Symbol.hasInstance]'.
 
 
 ==== tests/cases/conformance/es6/Symbols/symbolProperty44.ts (2 errors) ====
     class C {
         get [Symbol.hasInstance]() {
             ~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.hasInstance]'.
+!!! error TS2718: Duplicate declaration '[Symbol.hasInstance]'.
             return "";
         }
         get [Symbol.hasInstance]() {
             ~~~~~~~~~~~~~~~~~~~~
-!!! error TS2300: Duplicate identifier '[Symbol.hasInstance]'.
+!!! error TS2718: Duplicate declaration '[Symbol.hasInstance]'.
             return "";
         }
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty44.types b/tests/baselines/reference/symbolProperty44.types
index 2900c3eebc0f6..6206f1062062e 100644
--- a/tests/baselines/reference/symbolProperty44.types
+++ b/tests/baselines/reference/symbolProperty44.types
@@ -4,18 +4,18 @@ class C {
 
     get [Symbol.hasInstance]() {
 >[Symbol.hasInstance] : string
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
         return "";
 >"" : ""
     }
     get [Symbol.hasInstance]() {
 >[Symbol.hasInstance] : string
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty45.types b/tests/baselines/reference/symbolProperty45.types
index 674a262fcd633..4d5e4657f1868 100644
--- a/tests/baselines/reference/symbolProperty45.types
+++ b/tests/baselines/reference/symbolProperty45.types
@@ -4,18 +4,18 @@ class C {
 
     get [Symbol.hasInstance]() {
 >[Symbol.hasInstance] : string
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
         return "";
 >"" : ""
     }
     get [Symbol.toPrimitive]() {
 >[Symbol.toPrimitive] : string
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
         return "";
 >"" : ""
diff --git a/tests/baselines/reference/symbolProperty46.types b/tests/baselines/reference/symbolProperty46.types
index afdda60c51078..9ef3873ba591d 100644
--- a/tests/baselines/reference/symbolProperty46.types
+++ b/tests/baselines/reference/symbolProperty46.types
@@ -4,9 +4,9 @@ class C {
 
     get [Symbol.hasInstance]() {
 >[Symbol.hasInstance] : string
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
         return "";
 >"" : ""
@@ -14,9 +14,9 @@ class C {
     // Should take a string
     set [Symbol.hasInstance](x) {
 >[Symbol.hasInstance] : string
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >x : string
     }
 }
@@ -27,9 +27,9 @@ class C {
 >(new C) : C
 >new C : C
 >C : typeof C
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >0 : 0
 
 (new C)[Symbol.hasInstance] = "";
@@ -38,8 +38,8 @@ class C {
 >(new C) : C
 >new C : C
 >C : typeof C
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >"" : ""
 
diff --git a/tests/baselines/reference/symbolProperty47.types b/tests/baselines/reference/symbolProperty47.types
index af01c5e74a74a..59937f3208457 100644
--- a/tests/baselines/reference/symbolProperty47.types
+++ b/tests/baselines/reference/symbolProperty47.types
@@ -4,9 +4,9 @@ class C {
 
     get [Symbol.hasInstance]() {
 >[Symbol.hasInstance] : number
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 
         return "";
 >"" : ""
@@ -14,9 +14,9 @@ class C {
     // Should take a string
     set [Symbol.hasInstance](x: number) {
 >[Symbol.hasInstance] : number
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >x : number
     }
 }
@@ -27,9 +27,9 @@ class C {
 >(new C) : C
 >new C : C
 >C : typeof C
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >0 : 0
 
 (new C)[Symbol.hasInstance] = "";
@@ -38,8 +38,8 @@ class C {
 >(new C) : C
 >new C : C
 >C : typeof C
->Symbol.hasInstance : symbol
+>Symbol.hasInstance : unique symbol
 >Symbol : SymbolConstructor
->hasInstance : symbol
+>hasInstance : unique symbol
 >"" : ""
 
diff --git a/tests/baselines/reference/symbolProperty48.errors.txt b/tests/baselines/reference/symbolProperty48.errors.txt
deleted file mode 100644
index 8d52fa48a0728..0000000000000
--- a/tests/baselines/reference/symbolProperty48.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/es6/Symbols/symbolProperty48.ts(5,10): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/es6/Symbols/symbolProperty48.ts (1 errors) ====
-    module M {
-        var Symbol;
-    
-        class C {
-            [Symbol.iterator]() { }
-             ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-        }
-    }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty49.errors.txt b/tests/baselines/reference/symbolProperty49.errors.txt
deleted file mode 100644
index 8a15b359ee7e8..0000000000000
--- a/tests/baselines/reference/symbolProperty49.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/es6/Symbols/symbolProperty49.ts(5,10): error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/es6/Symbols/symbolProperty49.ts (1 errors) ====
-    module M {
-        export var Symbol;
-    
-        class C {
-            [Symbol.iterator]() { }
-             ~~~~~~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.iterator' must be of type 'symbol'.
-        }
-    }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty5.types b/tests/baselines/reference/symbolProperty5.types
index 398253128a701..58848f9ae237f 100644
--- a/tests/baselines/reference/symbolProperty5.types
+++ b/tests/baselines/reference/symbolProperty5.types
@@ -5,22 +5,22 @@ var x = {
 
     [Symbol.iterator]: 0,
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
     [Symbol.toPrimitive]() { },
 >[Symbol.toPrimitive] : () => void
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
     get [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : number
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return 0;
 >0 : 0
diff --git a/tests/baselines/reference/symbolProperty50.types b/tests/baselines/reference/symbolProperty50.types
index 659fd1d102f54..4635e723ec94f 100644
--- a/tests/baselines/reference/symbolProperty50.types
+++ b/tests/baselines/reference/symbolProperty50.types
@@ -10,8 +10,8 @@ module M {
 
         [Symbol.iterator]() { }
 >[Symbol.iterator] : () => void
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
     }
 }
diff --git a/tests/baselines/reference/symbolProperty51.types b/tests/baselines/reference/symbolProperty51.types
index c840469eb43f9..b2c6c53358b19 100644
--- a/tests/baselines/reference/symbolProperty51.types
+++ b/tests/baselines/reference/symbolProperty51.types
@@ -10,8 +10,8 @@ module M {
 
         [Symbol.iterator]() { }
 >[Symbol.iterator] : () => void
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
     }
 }
diff --git a/tests/baselines/reference/symbolProperty52.errors.txt b/tests/baselines/reference/symbolProperty52.errors.txt
index 5a44918d56489..4887130bbd419 100644
--- a/tests/baselines/reference/symbolProperty52.errors.txt
+++ b/tests/baselines/reference/symbolProperty52.errors.txt
@@ -1,10 +1,8 @@
 tests/cases/conformance/es6/Symbols/symbolProperty52.ts(2,13): error TS2339: Property 'nonsense' does not exist on type 'SymbolConstructor'.
-tests/cases/conformance/es6/Symbols/symbolProperty52.ts(5,1): error TS2322: Type '{}' is not assignable to type '{ [Symbol.nonsense]: number; }'.
-  Property '[Symbol.nonsense]' is missing in type '{}'.
 tests/cases/conformance/es6/Symbols/symbolProperty52.ts(7,12): error TS2339: Property 'nonsense' does not exist on type 'SymbolConstructor'.
 
 
-==== tests/cases/conformance/es6/Symbols/symbolProperty52.ts (3 errors) ====
+==== tests/cases/conformance/es6/Symbols/symbolProperty52.ts (2 errors) ====
     var obj = {
         [Symbol.nonsense]: 0
                 ~~~~~~~~
@@ -12,9 +10,6 @@ tests/cases/conformance/es6/Symbols/symbolProperty52.ts(7,12): error TS2339: Pro
     };
     
     obj = {};
-    ~~~
-!!! error TS2322: Type '{}' is not assignable to type '{ [Symbol.nonsense]: number; }'.
-!!! error TS2322:   Property '[Symbol.nonsense]' is missing in type '{}'.
     
     obj[Symbol.nonsense];
                ~~~~~~~~
diff --git a/tests/baselines/reference/symbolProperty52.types b/tests/baselines/reference/symbolProperty52.types
index d67595a22b76c..72ad1693a697e 100644
--- a/tests/baselines/reference/symbolProperty52.types
+++ b/tests/baselines/reference/symbolProperty52.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/Symbols/symbolProperty52.ts ===
 var obj = {
->obj : { [Symbol.nonsense]: number; }
->{    [Symbol.nonsense]: 0} : { [Symbol.nonsense]: number; }
+>obj : { [x: string]: number; }
+>{    [Symbol.nonsense]: 0} : { [x: string]: number; }
 
     [Symbol.nonsense]: 0
 >[Symbol.nonsense] : number
@@ -14,12 +14,12 @@ var obj = {
 
 obj = {};
 >obj = {} : {}
->obj : { [Symbol.nonsense]: number; }
+>obj : { [x: string]: number; }
 >{} : {}
 
 obj[Symbol.nonsense];
->obj[Symbol.nonsense] : any
->obj : { [Symbol.nonsense]: number; }
+>obj[Symbol.nonsense] : number
+>obj : { [x: string]: number; }
 >Symbol.nonsense : any
 >Symbol : SymbolConstructor
 >nonsense : any
diff --git a/tests/baselines/reference/symbolProperty53.types b/tests/baselines/reference/symbolProperty53.types
index 77dc3f16452f8..14fcc3e487545 100644
--- a/tests/baselines/reference/symbolProperty53.types
+++ b/tests/baselines/reference/symbolProperty53.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/Symbols/symbolProperty53.ts ===
 var obj = {
->obj : { [Symbol.for]: number; }
->{    [Symbol.for]: 0} : { [Symbol.for]: number; }
+>obj : {}
+>{    [Symbol.for]: 0} : {}
 
     [Symbol.for]: 0
 >[Symbol.for] : number
@@ -14,7 +14,7 @@ var obj = {
 
 obj[Symbol.for];
 >obj[Symbol.for] : any
->obj : { [Symbol.for]: number; }
+>obj : {}
 >Symbol.for : (key: string) => symbol
 >Symbol : SymbolConstructor
 >for : (key: string) => symbol
diff --git a/tests/baselines/reference/symbolProperty54.types b/tests/baselines/reference/symbolProperty54.types
index 2c6f9cd9e72df..8e4e9ab2bb737 100644
--- a/tests/baselines/reference/symbolProperty54.types
+++ b/tests/baselines/reference/symbolProperty54.types
@@ -1,7 +1,7 @@
 === tests/cases/conformance/es6/Symbols/symbolProperty54.ts ===
 var obj = {
->obj : { [Symbol.prototype]: number; }
->{    [Symbol.prototype]: 0} : { [Symbol.prototype]: number; }
+>obj : {}
+>{    [Symbol.prototype]: 0} : {}
 
     [Symbol.prototype]: 0
 >[Symbol.prototype] : number
diff --git a/tests/baselines/reference/symbolProperty55.types b/tests/baselines/reference/symbolProperty55.types
index 9316e5447e4e9..9aa40f7847418 100644
--- a/tests/baselines/reference/symbolProperty55.types
+++ b/tests/baselines/reference/symbolProperty55.types
@@ -5,9 +5,9 @@ var obj = {
 
     [Symbol.iterator]: 0
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
 };
@@ -22,9 +22,9 @@ module M {
     // The following should be of type 'any'. This is because even though obj has a property keyed by Symbol.iterator,
     // the key passed in here is the *wrong* Symbol.iterator. It is not the iterator property of the global Symbol.
     obj[Symbol.iterator];
->obj[Symbol.iterator] : any
+>obj[Symbol.iterator] : number
 >obj : { [Symbol.iterator]: number; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 }
diff --git a/tests/baselines/reference/symbolProperty56.types b/tests/baselines/reference/symbolProperty56.types
index 1f061739c4116..fc93f45b19833 100644
--- a/tests/baselines/reference/symbolProperty56.types
+++ b/tests/baselines/reference/symbolProperty56.types
@@ -5,9 +5,9 @@ var obj = {
 
     [Symbol.iterator]: 0
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
 };
diff --git a/tests/baselines/reference/symbolProperty57.types b/tests/baselines/reference/symbolProperty57.types
index 88dca83627fd9..ecea9c6ef51f5 100644
--- a/tests/baselines/reference/symbolProperty57.types
+++ b/tests/baselines/reference/symbolProperty57.types
@@ -5,9 +5,9 @@ var obj = {
 
     [Symbol.iterator]: 0
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
 };
diff --git a/tests/baselines/reference/symbolProperty58.errors.txt b/tests/baselines/reference/symbolProperty58.errors.txt
deleted file mode 100644
index 5f8b117a74c1b..0000000000000
--- a/tests/baselines/reference/symbolProperty58.errors.txt
+++ /dev/null
@@ -1,13 +0,0 @@
-tests/cases/conformance/es6/Symbols/symbolProperty58.ts(6,6): error TS2471: A computed property name of the form 'Symbol.foo' must be of type 'symbol'.
-
-
-==== tests/cases/conformance/es6/Symbols/symbolProperty58.ts (1 errors) ====
-    interface SymbolConstructor {
-        foo: string;
-    }
-    
-    var obj = {
-        [Symbol.foo]: 0
-         ~~~~~~~~~~
-!!! error TS2471: A computed property name of the form 'Symbol.foo' must be of type 'symbol'.
-    }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty58.types b/tests/baselines/reference/symbolProperty58.types
index 77edb8de1e72c..3d3c8bd55fe16 100644
--- a/tests/baselines/reference/symbolProperty58.types
+++ b/tests/baselines/reference/symbolProperty58.types
@@ -7,8 +7,8 @@ interface SymbolConstructor {
 }
 
 var obj = {
->obj : { [Symbol.foo]: number; }
->{    [Symbol.foo]: 0} : { [Symbol.foo]: number; }
+>obj : { [x: string]: number; }
+>{    [Symbol.foo]: 0} : { [x: string]: number; }
 
     [Symbol.foo]: 0
 >[Symbol.foo] : number
diff --git a/tests/baselines/reference/symbolProperty59.errors.txt b/tests/baselines/reference/symbolProperty59.errors.txt
index dfb2ece3d21f1..67deb77166147 100644
--- a/tests/baselines/reference/symbolProperty59.errors.txt
+++ b/tests/baselines/reference/symbolProperty59.errors.txt
@@ -1,9 +1,12 @@
+tests/cases/conformance/es6/Symbols/symbolProperty59.ts(2,5): error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
 tests/cases/conformance/es6/Symbols/symbolProperty59.ts(2,5): error TS2464: A computed property name must be of type 'string', 'number', 'symbol', or 'any'.
 
 
-==== tests/cases/conformance/es6/Symbols/symbolProperty59.ts (1 errors) ====
+==== tests/cases/conformance/es6/Symbols/symbolProperty59.ts (2 errors) ====
     interface I {
         [Symbol.keyFor]: string;
         ~~~~~~~~~~~~~~~
+!!! error TS1169: A computed property name in an interface must refer to an expression whose type is a literal type or a 'unique symbol' type.
+        ~~~~~~~~~~~~~~~
 !!! error TS2464: A computed property name must be of type 'string', 'number', 'symbol', or 'any'.
     }
\ No newline at end of file
diff --git a/tests/baselines/reference/symbolProperty6.js b/tests/baselines/reference/symbolProperty6.js
index ab9564c35e583..2361f4233c63a 100644
--- a/tests/baselines/reference/symbolProperty6.js
+++ b/tests/baselines/reference/symbolProperty6.js
@@ -9,11 +9,12 @@ class C {
 }
 
 //// [symbolProperty6.js]
+var _a;
 class C {
     constructor() {
-        this[Symbol.iterator] = 0;
+        this[_a] = 0;
     }
-    [Symbol.toPrimitive]() { }
+    [(_a = Symbol.iterator, Symbol.unscopables, Symbol.toPrimitive)]() { }
     get [Symbol.toStringTag]() {
         return 0;
     }
diff --git a/tests/baselines/reference/symbolProperty6.types b/tests/baselines/reference/symbolProperty6.types
index 8bdd05f01517a..c54543fe40905 100644
--- a/tests/baselines/reference/symbolProperty6.types
+++ b/tests/baselines/reference/symbolProperty6.types
@@ -4,28 +4,28 @@ class C {
 
     [Symbol.iterator] = 0;
 >[Symbol.iterator] : number
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >0 : 0
 
     [Symbol.unscopables]: number;
 >[Symbol.unscopables] : number
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 
     [Symbol.toPrimitive]() { }
 >[Symbol.toPrimitive] : () => void
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
     get [Symbol.toStringTag]() {
 >[Symbol.toStringTag] : number
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
         return 0;
 >0 : 0
diff --git a/tests/baselines/reference/symbolProperty60.types b/tests/baselines/reference/symbolProperty60.types
index cadbfcef1f430..7aa12ee2227f6 100644
--- a/tests/baselines/reference/symbolProperty60.types
+++ b/tests/baselines/reference/symbolProperty60.types
@@ -5,9 +5,9 @@ interface I1 {
 
     [Symbol.toStringTag]: string;
 >[Symbol.toStringTag] : string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     [key: string]: number;
 >key : string
@@ -18,9 +18,9 @@ interface I2 {
 
     [Symbol.toStringTag]: string;
 >[Symbol.toStringTag] : string
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
     [key: number]: boolean;
 >key : number
diff --git a/tests/baselines/reference/symbolProperty8.types b/tests/baselines/reference/symbolProperty8.types
index 936a2b9ec8872..5754ed38eea12 100644
--- a/tests/baselines/reference/symbolProperty8.types
+++ b/tests/baselines/reference/symbolProperty8.types
@@ -4,13 +4,13 @@ interface I {
 
     [Symbol.unscopables]: number;
 >[Symbol.unscopables] : number
->Symbol.unscopables : symbol
+>Symbol.unscopables : unique symbol
 >Symbol : SymbolConstructor
->unscopables : symbol
+>unscopables : unique symbol
 
     [Symbol.toPrimitive]();
 >[Symbol.toPrimitive] : () => any
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 }
diff --git a/tests/baselines/reference/symbolProperty9.js b/tests/baselines/reference/symbolProperty9.js
index e6c8f7299a9e8..85b3df51438dc 100644
--- a/tests/baselines/reference/symbolProperty9.js
+++ b/tests/baselines/reference/symbolProperty9.js
@@ -13,6 +13,7 @@ var c: C = i;
 //// [symbolProperty9.js]
 class C {
 }
+Symbol.iterator;
 var i;
 i = new C;
 var c = i;
diff --git a/tests/baselines/reference/symbolProperty9.types b/tests/baselines/reference/symbolProperty9.types
index b307677b2fabe..366a0d6b6f9b6 100644
--- a/tests/baselines/reference/symbolProperty9.types
+++ b/tests/baselines/reference/symbolProperty9.types
@@ -4,9 +4,9 @@ class C {
 
     [Symbol.iterator]: { x; y };
 >[Symbol.iterator] : { x: any; y: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 >y : any
 }
@@ -15,9 +15,9 @@ interface I {
 
     [Symbol.iterator]: { x };
 >[Symbol.iterator] : { x: any; }
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 >x : any
 }
 
diff --git a/tests/baselines/reference/symbolType2.types b/tests/baselines/reference/symbolType2.types
index 5da837f738e5e..fcc00973f2322 100644
--- a/tests/baselines/reference/symbolType2.types
+++ b/tests/baselines/reference/symbolType2.types
@@ -1,15 +1,15 @@
 === tests/cases/conformance/es6/Symbols/symbolType2.ts ===
 Symbol.isConcatSpreadable in {};
 >Symbol.isConcatSpreadable in {} : boolean
->Symbol.isConcatSpreadable : symbol
+>Symbol.isConcatSpreadable : unique symbol
 >Symbol : SymbolConstructor
->isConcatSpreadable : symbol
+>isConcatSpreadable : unique symbol
 >{} : {}
 
 "" in Symbol.toPrimitive;
 >"" in Symbol.toPrimitive : boolean
 >"" : ""
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
diff --git a/tests/baselines/reference/symbolType3.types b/tests/baselines/reference/symbolType3.types
index 6f31861fd936f..336440af93cae 100644
--- a/tests/baselines/reference/symbolType3.types
+++ b/tests/baselines/reference/symbolType3.types
@@ -6,21 +6,21 @@ var s = Symbol();
 
 delete Symbol.iterator;
 >delete Symbol.iterator : boolean
->Symbol.iterator : symbol
+>Symbol.iterator : unique symbol
 >Symbol : SymbolConstructor
->iterator : symbol
+>iterator : unique symbol
 
 void Symbol.toPrimitive;
 >void Symbol.toPrimitive : undefined
->Symbol.toPrimitive : symbol
+>Symbol.toPrimitive : unique symbol
 >Symbol : SymbolConstructor
->toPrimitive : symbol
+>toPrimitive : unique symbol
 
 typeof Symbol.toStringTag;
 >typeof Symbol.toStringTag : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
 ++s;
 >++s : number
diff --git a/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.js b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.js
new file mode 100644
index 0000000000000..30c2b1c639e8a
--- /dev/null
+++ b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.js
@@ -0,0 +1,14 @@
+//// [typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts]
+const s = Symbol("s");
+
+interface I {
+    n: number;
+    [s]: string;
+    [Symbol.iterator](): IterableIterator<[string, string]>;
+}
+
+type K = keyof I;
+type T = I[K];
+
+//// [typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.js]
+var s = Symbol("s");
diff --git a/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.symbols b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.symbols
new file mode 100644
index 0000000000000..b8a91d04fa213
--- /dev/null
+++ b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.symbols
@@ -0,0 +1,32 @@
+=== tests/cases/compiler/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts ===
+const s = Symbol("s");
+>s : Symbol(s, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 0, 5))
+>Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(lib.es2015.symbol.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))
+
+interface I {
+>I : Symbol(I, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 0, 22))
+
+    n: number;
+>n : Symbol(I.n, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 2, 13))
+
+    [s]: string;
+>[s] : Symbol(I[s], Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 3, 14))
+>s : Symbol(s, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 0, 5))
+
+    [Symbol.iterator](): IterableIterator<[string, string]>;
+>[Symbol.iterator] : Symbol(I[Symbol.iterator], Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 4, 16))
+>Symbol.iterator : Symbol(SymbolConstructor.iterator, Decl(lib.es2015.iterable.d.ts, --, --))
+>Symbol : Symbol(Symbol, Decl(lib.es5.d.ts, --, --), Decl(lib.es2015.symbol.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --))
+>iterator : Symbol(SymbolConstructor.iterator, Decl(lib.es2015.iterable.d.ts, --, --))
+>IterableIterator : Symbol(IterableIterator, Decl(lib.es2015.iterable.d.ts, --, --))
+}
+
+type K = keyof I;
+>K : Symbol(K, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 6, 1))
+>I : Symbol(I, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 0, 22))
+
+type T = I[K];
+>T : Symbol(T, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 8, 17))
+>I : Symbol(I, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 0, 22))
+>K : Symbol(K, Decl(typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts, 6, 1))
+
diff --git a/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.types b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.types
new file mode 100644
index 0000000000000..ee1707fec01e2
--- /dev/null
+++ b/tests/baselines/reference/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.types
@@ -0,0 +1,34 @@
+=== tests/cases/compiler/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts ===
+const s = Symbol("s");
+>s : unique symbol
+>Symbol("s") : unique symbol
+>Symbol : SymbolConstructor
+>"s" : "s"
+
+interface I {
+>I : I
+
+    n: number;
+>n : number
+
+    [s]: string;
+>[s] : string
+>s : unique symbol
+
+    [Symbol.iterator](): IterableIterator<[string, string]>;
+>[Symbol.iterator] : () => IterableIterator<[string, string]>
+>Symbol.iterator : unique symbol
+>Symbol : SymbolConstructor
+>iterator : unique symbol
+>IterableIterator : IterableIterator<T>
+}
+
+type K = keyof I;
+>K : unique symbol | unique symbol | "n"
+>I : I
+
+type T = I[K];
+>T : string | number | (() => IterableIterator<[string, string]>)
+>I : I
+>K : unique symbol | unique symbol | "n"
+
diff --git a/tests/baselines/reference/useSharedArrayBuffer4.types b/tests/baselines/reference/useSharedArrayBuffer4.types
index c3602b26b63b6..9776dc1ae3d3e 100644
--- a/tests/baselines/reference/useSharedArrayBuffer4.types
+++ b/tests/baselines/reference/useSharedArrayBuffer4.types
@@ -18,17 +18,17 @@ var species = foge[Symbol.species];
 >species : SharedArrayBuffer
 >foge[Symbol.species] : SharedArrayBuffer
 >foge : SharedArrayBuffer
->Symbol.species : symbol
+>Symbol.species : unique symbol
 >Symbol : SymbolConstructor
->species : symbol
+>species : unique symbol
 
 var stringTag = foge[Symbol.toStringTag];
 >stringTag : "SharedArrayBuffer"
 >foge[Symbol.toStringTag] : "SharedArrayBuffer"
 >foge : SharedArrayBuffer
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
 var len = foge.byteLength;
 >len : number
diff --git a/tests/baselines/reference/useSharedArrayBuffer5.types b/tests/baselines/reference/useSharedArrayBuffer5.types
index 48db8b739f938..1d3f896012b18 100644
--- a/tests/baselines/reference/useSharedArrayBuffer5.types
+++ b/tests/baselines/reference/useSharedArrayBuffer5.types
@@ -9,15 +9,15 @@ var species = foge[Symbol.species];
 >species : SharedArrayBuffer
 >foge[Symbol.species] : SharedArrayBuffer
 >foge : SharedArrayBuffer
->Symbol.species : symbol
+>Symbol.species : unique symbol
 >Symbol : SymbolConstructor
->species : symbol
+>species : unique symbol
 
 var stringTag = foge[Symbol.toStringTag];
 >stringTag : "SharedArrayBuffer"
 >foge[Symbol.toStringTag] : "SharedArrayBuffer"
 >foge : SharedArrayBuffer
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
diff --git a/tests/baselines/reference/useSharedArrayBuffer6.types b/tests/baselines/reference/useSharedArrayBuffer6.types
index af80ec432f388..73196aacacdca 100644
--- a/tests/baselines/reference/useSharedArrayBuffer6.types
+++ b/tests/baselines/reference/useSharedArrayBuffer6.types
@@ -9,15 +9,15 @@ var species = foge[Symbol.species];
 >species : SharedArrayBuffer
 >foge[Symbol.species] : SharedArrayBuffer
 >foge : SharedArrayBuffer
->Symbol.species : symbol
+>Symbol.species : unique symbol
 >Symbol : SymbolConstructor
->species : symbol
+>species : unique symbol
 
 var stringTag = foge[Symbol.toStringTag];
 >stringTag : "SharedArrayBuffer"
 >foge[Symbol.toStringTag] : "SharedArrayBuffer"
 >foge : SharedArrayBuffer
->Symbol.toStringTag : symbol
+>Symbol.toStringTag : unique symbol
 >Symbol : SymbolConstructor
->toStringTag : symbol
+>toStringTag : unique symbol
 
diff --git a/tests/cases/compiler/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts b/tests/cases/compiler/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts
new file mode 100644
index 0000000000000..890c84667ef7b
--- /dev/null
+++ b/tests/cases/compiler/typesOfInterfaceContainUniqueSymbolsFromWellKnownSymbols.ts
@@ -0,0 +1,11 @@
+// @lib: es6
+const s = Symbol("s");
+
+interface I {
+    n: number;
+    [s]: string;
+    [Symbol.iterator](): IterableIterator<[string, string]>;
+}
+
+type K = keyof I;
+type T = I[K];
\ No newline at end of file
diff --git a/tests/cases/conformance/Symbols/ES5SymbolProperty5.ts b/tests/cases/conformance/Symbols/ES5SymbolProperty5.ts
index ec46ddad21dc1..6a5dd9ea3fcdd 100644
--- a/tests/cases/conformance/Symbols/ES5SymbolProperty5.ts
+++ b/tests/cases/conformance/Symbols/ES5SymbolProperty5.ts
@@ -1,5 +1,5 @@
 //@target: ES5
-var Symbol: { iterator: symbol };
+var Symbol: { readonly iterator: unique symbol };
 
 class C {
     [Symbol.iterator]() { }
diff --git a/tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts b/tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts
index b832d57855ed2..7f0f236c55610 100644
--- a/tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts
+++ b/tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck10.ts
@@ -1,4 +1,5 @@
 //@target: ES5
+//@lib: es6
 
 // In ES3/5, you cannot for...of over an arbitrary iterable.
 class StringIterator {
diff --git a/tests/cases/fourslash/codeFixClassImplementInterfaceComputedPropertyNameWellKnownSymbols.ts b/tests/cases/fourslash/codeFixClassImplementInterfaceComputedPropertyNameWellKnownSymbols.ts
index 2bc7a738258a4..6916a5d58ba59 100644
--- a/tests/cases/fourslash/codeFixClassImplementInterfaceComputedPropertyNameWellKnownSymbols.ts
+++ b/tests/cases/fourslash/codeFixClassImplementInterfaceComputedPropertyNameWellKnownSymbols.ts
@@ -1,7 +1,19 @@
 /// <reference path='fourslash.ts' />
 
-// @lib: es2017
-
+// @noLib: true
+////declare const Symbol: {
+////    readonly hasInstance: unique symbol,
+////    readonly isConcatSpreadable: unique symbol,
+////    readonly iterator: unique symbol,
+////    readonly match: unique symbol,
+////    readonly replace: unique symbol,
+////    readonly search: unique symbol,
+////    readonly species: unique symbol,
+////    readonly split: unique symbol,
+////    readonly toPrimitive: unique symbol,
+////    readonly toStringTag: unique symbol,
+////    readonly unscopables: unique symbol,
+////};
 ////interface I<Species> {
 ////    [Symbol.hasInstance](o: any): boolean;
 ////    [Symbol.isConcatSpreadable]: boolean;
@@ -22,7 +34,20 @@
 verify.codeFix({
     description: "Implement interface 'I<number>'",
     newFileContent:
-`interface I<Species> {
+`declare const Symbol: {
+    readonly hasInstance: unique symbol,
+    readonly isConcatSpreadable: unique symbol,
+    readonly iterator: unique symbol,
+    readonly match: unique symbol,
+    readonly replace: unique symbol,
+    readonly search: unique symbol,
+    readonly species: unique symbol,
+    readonly split: unique symbol,
+    readonly toPrimitive: unique symbol,
+    readonly toStringTag: unique symbol,
+    readonly unscopables: unique symbol,
+};
+interface I<Species> {
     [Symbol.hasInstance](o: any): boolean;
     [Symbol.isConcatSpreadable]: boolean;
     [Symbol.iterator](): any;
@@ -64,7 +89,7 @@ class C implements I<number> {
     [Symbol.toPrimitive](hint: any) {
         throw new Error("Method not implemented.");
     }
-    [Symbol.toStringTag]: string\;
+    [Symbol.toStringTag]: string;
     [Symbol.unscopables]: any;
 }`,
 });