From 43d7b9a2fad31fa4d038cc02c3f4d1d75e38c4f6 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Thu, 26 Apr 2018 14:00:10 -0700
Subject: [PATCH 1/5] Always export typedefs

This actually just required deleting a check in declareModuleMembers
and checking for external AND commonjs modules in a couple of places.

However, while experimenting with this feature, I discovered that even
previously-exported typedefs would only be exported if they came after a
commonjs export node. So I added a commonjs check to the pass in the
parser. It will not catch nested module.exports, but it will catch
top-level assignments.

The new test tests both changes.
---
 src/compiler/binder.ts                        |  7 +-
 src/compiler/parser.ts                        | 13 +++
 src/harness/harness.ts                        |  2 +-
 .../reference/jsdocTypedefNoCrash.symbols     |  2 +-
 .../reference/typedefCrossModule.symbols      | 70 +++++++++++++++
 .../reference/typedefCrossModule.types        | 88 +++++++++++++++++++
 .../conformance/jsdoc/typedefCrossModule.ts   | 44 ++++++++++
 7 files changed, 220 insertions(+), 6 deletions(-)
 create mode 100644 tests/baselines/reference/typedefCrossModule.symbols
 create mode 100644 tests/baselines/reference/typedefCrossModule.types
 create mode 100644 tests/cases/conformance/jsdoc/typedefCrossModule.ts

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 2557e3b707827..2e94c84596717 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -450,8 +450,7 @@ namespace ts {
                 //       and this case is specially handled. Module augmentations should only be merged with original module definition
                 //       and should never be merged directly with other augmentation, and the latter case would be possible if automatic merge is allowed.
                 if (node.kind === SyntaxKind.JSDocTypedefTag) Debug.assert(isInJavaScriptFile(node)); // We shouldn't add symbols for JSDoc nodes if not in a JS file.
-                const isJSDocTypedefInJSDocNamespace = isJSDocTypedefTag(node) && node.name && node.name.kind === SyntaxKind.Identifier && node.name.isInJSDocNamespace;
-                if ((!isAmbientModule(node) && (hasExportModifier || container.flags & NodeFlags.ExportContext)) || isJSDocTypedefInJSDocNamespace) {
+                if ((!isAmbientModule(node) && (hasExportModifier || container.flags & NodeFlags.ExportContext)) || isJSDocTypedefTag(node)) {
                     if (hasModifier(node, ModifierFlags.Default) && !getDeclarationName(node)) {
                         return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes); // No local symbol for an unnamed default!
                     }
@@ -1727,7 +1726,7 @@ namespace ts {
                     declareModuleMember(node, symbolFlags, symbolExcludes);
                     break;
                 case SyntaxKind.SourceFile:
-                    if (isExternalModule(<SourceFile>container)) {
+                    if (isExternalOrCommonJsModule(<SourceFile>container)) {
                         declareModuleMember(node, symbolFlags, symbolExcludes);
                         break;
                     }
@@ -2211,7 +2210,7 @@ namespace ts {
 
         function bindSourceFileIfExternalModule() {
             setExportContextFlag(file);
-            if (isExternalModule(file)) {
+            if (isExternalOrCommonJsModule(file)) {
                 bindSourceFileAsExternalModule();
             }
         }
diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index 8547eb171147a..b67efe9dfb8c9 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -6116,6 +6116,19 @@ namespace ts {
                     || node.kind === SyntaxKind.ExportDeclaration
                     ? node
                     : undefined);
+            if (isInJavaScriptFile(sourceFile) && !sourceFile.externalModuleIndicator) {
+                sourceFile.commonJsModuleIndicator = forEach(sourceFile.statements, isCommonJsModuleIndicator);
+            }
+        }
+
+        function isCommonJsModuleIndicator(statement: Statement) {
+            if (isExpressionStatement(statement) && isBinaryExpression(statement.expression)) {
+                const special = getSpecialPropertyAssignmentKind(statement.expression);
+                if (special === SpecialPropertyAssignmentKind.ModuleExports ||
+                    special === SpecialPropertyAssignmentKind.ExportsProperty) {
+                    return statement.expression.left;
+                }
+            }
         }
 
         const enum ParsingContext {
diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 9fe26ed51c3ba..c955c1acb59d2 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -217,7 +217,7 @@ namespace Utils {
             for (const childName in node) {
                 if (childName === "parent" || childName === "nextContainer" || childName === "modifiers" || childName === "externalModuleIndicator" ||
                     // for now ignore jsdoc comments
-                    childName === "jsDocComment" || childName === "checkJsDirective") {
+                    childName === "jsDocComment" || childName === "checkJsDirective" || childName === "commonJsModuleIndicator") {
                     continue;
                 }
                 const child = (<any>node)[childName];
diff --git a/tests/baselines/reference/jsdocTypedefNoCrash.symbols b/tests/baselines/reference/jsdocTypedefNoCrash.symbols
index 8724c9da8d171..43ba5734073cc 100644
--- a/tests/baselines/reference/jsdocTypedefNoCrash.symbols
+++ b/tests/baselines/reference/jsdocTypedefNoCrash.symbols
@@ -4,5 +4,5 @@
  * }}
  */
 export const foo = 5;
->foo : Symbol(foo, Decl(export.js, 4, 12))
+>foo : Symbol(foo, Decl(export.js, 1, 3), Decl(export.js, 4, 12))
 
diff --git a/tests/baselines/reference/typedefCrossModule.symbols b/tests/baselines/reference/typedefCrossModule.symbols
new file mode 100644
index 0000000000000..2ba91903ba3ad
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule.symbols
@@ -0,0 +1,70 @@
+=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
+declare var module: { exports: any};
+>module : Symbol(module, Decl(commonjs.d.ts, 0, 11))
+>exports : Symbol(exports, Decl(commonjs.d.ts, 0, 21))
+
+=== tests/cases/conformance/jsdoc/mod1.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+module.exports = C
+>module.exports : Symbol(exports, Decl(commonjs.d.ts, 0, 21))
+>module : Symbol(export=, Decl(mod1.js, 0, 0))
+>exports : Symbol(export=, Decl(mod1.js, 0, 0))
+>C : Symbol(C, Decl(mod1.js, 4, 18))
+
+function C() {
+>C : Symbol(C, Decl(mod1.js, 4, 18))
+
+    this.p = 1
+>p : Symbol(C.p, Decl(mod1.js, 5, 14))
+}
+
+=== tests/cases/conformance/jsdoc/mod2.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+export function C() {
+>C : Symbol(C, Decl(mod2.js, 0, 0))
+
+    this.p = 1
+>p : Symbol(C.p, Decl(mod2.js, 5, 21))
+}
+
+=== tests/cases/conformance/jsdoc/mod3.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+exports.C = function() {
+>exports.C : Symbol(C, Decl(mod3.js, 0, 0))
+>exports : Symbol(C, Decl(mod3.js, 0, 0))
+>C : Symbol(C, Decl(mod3.js, 0, 0))
+
+    this.p = 1
+>p : Symbol(C.p, Decl(mod3.js, 5, 24))
+}
+
+=== tests/cases/conformance/jsdoc/use.js ===
+/** @type {import('./mod1').Both} */
+var both1 = { type: 'a', x: 1 };
+>both1 : Symbol(both1, Decl(use.js, 1, 3))
+>type : Symbol(type, Decl(use.js, 1, 13))
+>x : Symbol(x, Decl(use.js, 1, 24))
+
+/** @type {import('./mod2').Both} */
+var both2 = both1;
+>both2 : Symbol(both2, Decl(use.js, 3, 3))
+>both1 : Symbol(both1, Decl(use.js, 1, 3))
+
+/** @type {import('./mod3').Both} */
+var both3 = both2;
+>both3 : Symbol(both3, Decl(use.js, 5, 3))
+>both2 : Symbol(both2, Decl(use.js, 3, 3))
+
+
+
diff --git a/tests/baselines/reference/typedefCrossModule.types b/tests/baselines/reference/typedefCrossModule.types
new file mode 100644
index 0000000000000..665fa4989918b
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule.types
@@ -0,0 +1,88 @@
+=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
+declare var module: { exports: any};
+>module : { exports: any; }
+>exports : any
+
+=== tests/cases/conformance/jsdoc/mod1.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+module.exports = C
+>module.exports = C : typeof C
+>module.exports : any
+>module : { exports: any; }
+>exports : any
+>C : typeof C
+
+function C() {
+>C : typeof C
+
+    this.p = 1
+>this.p = 1 : 1
+>this.p : any
+>this : any
+>p : any
+>1 : 1
+}
+
+=== tests/cases/conformance/jsdoc/mod2.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+export function C() {
+>C : typeof C
+
+    this.p = 1
+>this.p = 1 : 1
+>this.p : any
+>this : any
+>p : any
+>1 : 1
+}
+
+=== tests/cases/conformance/jsdoc/mod3.js ===
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+exports.C = function() {
+>exports.C = function() {    this.p = 1} : typeof C
+>exports.C : typeof C
+>exports : typeof import("tests/cases/conformance/jsdoc/mod3")
+>C : typeof C
+>function() {    this.p = 1} : typeof C
+
+    this.p = 1
+>this.p = 1 : 1
+>this.p : any
+>this : any
+>p : any
+>1 : 1
+}
+
+=== tests/cases/conformance/jsdoc/use.js ===
+/** @type {import('./mod1').Both} */
+var both1 = { type: 'a', x: 1 };
+>both1 : { type: "a"; x: 1; } | { type: "b"; y: 1; }
+>{ type: 'a', x: 1 } : { type: "a"; x: 1; }
+>type : "a"
+>'a' : "a"
+>x : 1
+>1 : 1
+
+/** @type {import('./mod2').Both} */
+var both2 = both1;
+>both2 : { type: "a"; x: 1; } | { type: "b"; y: 1; }
+>both1 : { type: "a"; x: 1; }
+
+/** @type {import('./mod3').Both} */
+var both3 = both2;
+>both3 : { type: "a"; x: 1; } | { type: "b"; y: 1; }
+>both2 : { type: "a"; x: 1; }
+
+
+
diff --git a/tests/cases/conformance/jsdoc/typedefCrossModule.ts b/tests/cases/conformance/jsdoc/typedefCrossModule.ts
new file mode 100644
index 0000000000000..772a41da7bf82
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/typedefCrossModule.ts
@@ -0,0 +1,44 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: commonjs.d.ts
+declare var module: { exports: any};
+// @Filename: mod1.js
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+module.exports = C
+function C() {
+    this.p = 1
+}
+
+// @Filename: mod2.js
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+export function C() {
+    this.p = 1
+}
+
+// @Filename: mod3.js
+/// <reference path="./commonjs.d.ts"/>
+/** @typedef {{ type: "a", x: 1 }} A */
+/** @typedef {{ type: "b", y: 1 }} B */
+/** @typedef {A | B} Both */
+
+exports.C = function() {
+    this.p = 1
+}
+
+// @Filename: use.js
+/** @type {import('./mod1').Both} */
+var both1 = { type: 'a', x: 1 };
+/** @type {import('./mod2').Both} */
+var both2 = both1;
+/** @type {import('./mod3').Both} */
+var both3 = both2;
+
+

From 539afc0bf023d4a338cff99ed3f6b8065f3a5b03 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Fri, 27 Apr 2018 10:10:34 -0700
Subject: [PATCH 2/5] Post-bind typedef instead of pre-checking for commonjs

---
 src/compiler/binder.ts                        | 25 +++++++++++++++++--
 src/compiler/parser.ts                        | 13 ----------
 .../reference/jsdocTypedefNoCrash.symbols     |  2 +-
 3 files changed, 24 insertions(+), 16 deletions(-)

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 2e94c84596717..136a86d0429bd 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -118,6 +118,7 @@ namespace ts {
         let thisParentContainer: Node; // Container one level up
         let blockScopeContainer: Node;
         let lastContainer: Node;
+        let delayedTypedefs: { typedef: JSDocTypedefTag, container: Node, lastContainer: Node, blockScopeContainer: Node, parent: Node }[];
         let seenThisKeyword: boolean;
 
         // state used by control flow analysis
@@ -176,6 +177,7 @@ namespace ts {
                 bind(file);
                 file.symbolCount = symbolCount;
                 file.classifiableNames = classifiableNames;
+                delayedBindJSDocTypedefTag();
             }
 
             file = undefined;
@@ -186,6 +188,7 @@ namespace ts {
             thisParentContainer = undefined;
             blockScopeContainer = undefined;
             lastContainer = undefined;
+            delayedTypedefs = undefined;
             seenThisKeyword = false;
             currentFlow = undefined;
             currentBreakTarget = undefined;
@@ -1744,6 +1747,24 @@ namespace ts {
             bindBlockScopedDeclaration(node, SymbolFlags.BlockScopedVariable, SymbolFlags.BlockScopedVariableExcludes);
         }
 
+        function delayedBindJSDocTypedefTag() {
+            if (!delayedTypedefs) {
+                return;
+            }
+            const saveContainer = container;
+            const saveLastContainer = lastContainer;
+            const saveBlockScopeContainer = blockScopeContainer;
+            const saveParent = parent;
+            for (const delay of delayedTypedefs) {
+                ({ container, lastContainer, blockScopeContainer, parent } = delay);
+                bindBlockScopedDeclaration(delay.typedef, SymbolFlags.TypeAlias, SymbolFlags.TypeAliasExcludes);
+            }
+            container = saveContainer;
+            lastContainer = saveLastContainer;
+            blockScopeContainer = saveBlockScopeContainer;
+            parent = saveParent;
+        }
+
         // The binder visits every node in the syntax tree so it is a convenient place to perform a single localized
         // check for reserved words used as identifiers in strict mode code.
         function checkStrictModeIdentifier(node: Identifier) {
@@ -2193,7 +2214,7 @@ namespace ts {
                 case SyntaxKind.JSDocTypedefTag: {
                     const { fullName } = node as JSDocTypedefTag;
                     if (!fullName || fullName.kind === SyntaxKind.Identifier) {
-                        return bindBlockScopedDeclaration(<Declaration>node, SymbolFlags.TypeAlias, SymbolFlags.TypeAliasExcludes);
+                        (delayedTypedefs || (delayedTypedefs = [])).push({ typedef: node as JSDocTypedefTag, container, lastContainer, blockScopeContainer, parent });
                     }
                     break;
                 }
@@ -2210,7 +2231,7 @@ namespace ts {
 
         function bindSourceFileIfExternalModule() {
             setExportContextFlag(file);
-            if (isExternalOrCommonJsModule(file)) {
+            if (isExternalModule(file)) {
                 bindSourceFileAsExternalModule();
             }
         }
diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index b67efe9dfb8c9..8547eb171147a 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -6116,19 +6116,6 @@ namespace ts {
                     || node.kind === SyntaxKind.ExportDeclaration
                     ? node
                     : undefined);
-            if (isInJavaScriptFile(sourceFile) && !sourceFile.externalModuleIndicator) {
-                sourceFile.commonJsModuleIndicator = forEach(sourceFile.statements, isCommonJsModuleIndicator);
-            }
-        }
-
-        function isCommonJsModuleIndicator(statement: Statement) {
-            if (isExpressionStatement(statement) && isBinaryExpression(statement.expression)) {
-                const special = getSpecialPropertyAssignmentKind(statement.expression);
-                if (special === SpecialPropertyAssignmentKind.ModuleExports ||
-                    special === SpecialPropertyAssignmentKind.ExportsProperty) {
-                    return statement.expression.left;
-                }
-            }
         }
 
         const enum ParsingContext {
diff --git a/tests/baselines/reference/jsdocTypedefNoCrash.symbols b/tests/baselines/reference/jsdocTypedefNoCrash.symbols
index 43ba5734073cc..51f5fdcc259fc 100644
--- a/tests/baselines/reference/jsdocTypedefNoCrash.symbols
+++ b/tests/baselines/reference/jsdocTypedefNoCrash.symbols
@@ -4,5 +4,5 @@
  * }}
  */
 export const foo = 5;
->foo : Symbol(foo, Decl(export.js, 1, 3), Decl(export.js, 4, 12))
+>foo : Symbol(foo, Decl(export.js, 4, 12), Decl(export.js, 1, 3))
 

From 777b5a089b88d1c2501d55a1393ed2a62d72fd1a Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Fri, 27 Apr 2018 16:00:47 -0700
Subject: [PATCH 3/5] Duplicate identifier errors

---
 src/compiler/binder.ts                        |  5 +-
 src/compiler/checker.ts                       | 10 ++
 .../reference/typedefCrossModule2.errors.txt  | 62 +++++++++++++
 .../reference/typedefCrossModule2.symbols     | 77 ++++++++++++++++
 .../reference/typedefCrossModule2.types       | 92 +++++++++++++++++++
 .../conformance/jsdoc/typedefCrossModule2.ts  | 45 +++++++++
 6 files changed, 290 insertions(+), 1 deletion(-)
 create mode 100644 tests/baselines/reference/typedefCrossModule2.errors.txt
 create mode 100644 tests/baselines/reference/typedefCrossModule2.symbols
 create mode 100644 tests/baselines/reference/typedefCrossModule2.types
 create mode 100644 tests/cases/conformance/jsdoc/typedefCrossModule2.ts

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 136a86d0429bd..d470a9d778509 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -2324,7 +2324,10 @@ namespace ts {
                 return s;
             });
             if (symbol) {
-                declareSymbol(symbol.exports, symbol, lhs, SymbolFlags.Property | SymbolFlags.ExportValue, SymbolFlags.None);
+                const flags = isClassExpression(node.right) ?
+                    SymbolFlags.Property | SymbolFlags.ExportValue | SymbolFlags.Class :
+                    SymbolFlags.Property | SymbolFlags.ExportValue;
+                declareSymbol(symbol.exports, symbol, lhs, flags, SymbolFlags.None);
             }
         }
 
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index fa485b68a9237..afd5ba66c24e5 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -27220,6 +27220,16 @@ namespace ts {
                 let currentKind: Flags;
                 switch (prop.kind) {
                     case SyntaxKind.PropertyAssignment:
+                        if (isClassExpression(prop.initializer)) {
+                            const n = prop.name;
+                            const sn = getTextOfPropertyName(n);
+                            const symbol = resolveName(n, sn, SymbolFlags.Type, undefined, sn, /*isUse*/ false);
+                            if (symbol) {
+                                grammarErrorOnNode(symbol.declarations[0], Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(sn));
+                                return grammarErrorOnNode(n, Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(sn));
+                            }
+                        }
+                       // falls through
                     case SyntaxKind.ShorthandPropertyAssignment:
                         // Grammar checking for computedPropertyName and shorthandPropertyAssignment
                         checkGrammarForInvalidQuestionMark(prop.questionToken, Diagnostics.An_object_member_cannot_be_declared_optional);
diff --git a/tests/baselines/reference/typedefCrossModule2.errors.txt b/tests/baselines/reference/typedefCrossModule2.errors.txt
new file mode 100644
index 0000000000000..1d7fbb3bde265
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule2.errors.txt
@@ -0,0 +1,62 @@
+tests/cases/conformance/jsdoc/mod1.js(5,23): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod1.js(6,7): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod1.js(8,23): error TS2300: Duplicate identifier 'Bar'.
+tests/cases/conformance/jsdoc/mod1.js(9,9): error TS2300: Duplicate identifier 'Bar'.
+tests/cases/conformance/jsdoc/mod1.js(11,5): error TS2300: Duplicate identifier 'Baz'.
+tests/cases/conformance/jsdoc/mod1.js(13,5): error TS2300: Duplicate identifier 'Baz'.
+
+
+==== tests/cases/conformance/jsdoc/use.js (0 errors) ====
+    var mod = require('./mod1.js');
+    /** @type {import("./mod1.js").Baz} */
+    var b;
+    /** @type {mod.Baz} */
+    var bb;
+    var bbb = new mod.Baz();
+    
+==== tests/cases/conformance/jsdoc/commonjs.d.ts (0 errors) ====
+    declare function require(name: string): any;
+    declare var module: { exports: any};
+    declare var exports: any;
+    
+==== tests/cases/conformance/jsdoc/mod1.js (6 errors) ====
+    /// <reference path="./commonjs.d.ts"/>
+    
+    // error
+    
+    /** @typedef {number} Foo */
+                          ~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    class Foo { } // should error
+          ~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    
+    /** @typedef {number} Bar */
+                          ~~~
+!!! error TS2300: Duplicate identifier 'Bar'.
+    exports.Bar = class { }
+            ~~~
+!!! error TS2300: Duplicate identifier 'Bar'.
+    
+    /** @typedef {number} Baz */
+        ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2300: Duplicate identifier 'Baz'.
+    module.exports = {
+        Baz: class { }
+        ~~~
+!!! error TS2300: Duplicate identifier 'Baz'.
+    }
+    
+    // ok
+    
+    /** @typedef {number} Qux */
+    var Qux = 2;
+    
+    /** @typedef {number} Quid */
+    exports.Quid = 2;
+    
+    /** @typedef {number} Quack */
+    module.exports = {
+        Quack: 2
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/typedefCrossModule2.symbols b/tests/baselines/reference/typedefCrossModule2.symbols
new file mode 100644
index 0000000000000..5c51828176b97
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule2.symbols
@@ -0,0 +1,77 @@
+=== tests/cases/conformance/jsdoc/use.js ===
+var mod = require('./mod1.js');
+>mod : Symbol(mod, Decl(use.js, 0, 3))
+>require : Symbol(require, Decl(commonjs.d.ts, 0, 0))
+>'./mod1.js' : Symbol("tests/cases/conformance/jsdoc/mod1", Decl(mod1.js, 0, 0))
+
+/** @type {import("./mod1.js").Baz} */
+var b;
+>b : Symbol(b, Decl(use.js, 2, 3))
+
+/** @type {mod.Baz} */
+var bb;
+>bb : Symbol(bb, Decl(use.js, 4, 3))
+
+var bbb = new mod.Baz();
+>bbb : Symbol(bbb, Decl(use.js, 5, 3))
+>mod : Symbol(mod, Decl(use.js, 0, 3))
+
+=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
+declare function require(name: string): any;
+>require : Symbol(require, Decl(commonjs.d.ts, 0, 0))
+>name : Symbol(name, Decl(commonjs.d.ts, 0, 25))
+
+declare var module: { exports: any};
+>module : Symbol(module, Decl(commonjs.d.ts, 1, 11))
+>exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
+
+declare var exports: any;
+>exports : Symbol(exports, Decl(commonjs.d.ts, 2, 11))
+
+=== tests/cases/conformance/jsdoc/mod1.js ===
+/// <reference path="./commonjs.d.ts"/>
+
+// error
+
+/** @typedef {number} Foo */
+class Foo { } // should error
+>Foo : Symbol(Foo, Decl(mod1.js, 0, 0))
+
+/** @typedef {number} Bar */
+exports.Bar = class { }
+>exports.Bar : Symbol(Bar, Decl(mod1.js, 5, 13))
+>exports : Symbol(Bar, Decl(mod1.js, 5, 13))
+>Bar : Symbol(Bar, Decl(mod1.js, 5, 13))
+
+/** @typedef {number} Baz */
+module.exports = {
+>module.exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
+>module : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+>exports : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+
+    Baz: class { }
+>Baz : Symbol(Baz, Decl(mod1.js, 11, 18))
+}
+
+// ok
+
+/** @typedef {number} Qux */
+var Qux = 2;
+>Qux : Symbol(Qux, Decl(mod1.js, 18, 3), Decl(mod1.js, 17, 4))
+
+/** @typedef {number} Quid */
+exports.Quid = 2;
+>exports.Quid : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
+>exports : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
+>Quid : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
+
+/** @typedef {number} Quack */
+module.exports = {
+>module.exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
+>module : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+>exports : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+
+    Quack: 2
+>Quack : Symbol(Quack, Decl(mod1.js, 24, 18))
+}
+
diff --git a/tests/baselines/reference/typedefCrossModule2.types b/tests/baselines/reference/typedefCrossModule2.types
new file mode 100644
index 0000000000000..2cf4314c33599
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule2.types
@@ -0,0 +1,92 @@
+=== tests/cases/conformance/jsdoc/use.js ===
+var mod = require('./mod1.js');
+>mod : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
+>require('./mod1.js') : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
+>require : (name: string) => any
+>'./mod1.js' : "./mod1.js"
+
+/** @type {import("./mod1.js").Baz} */
+var b;
+>b : number
+
+/** @type {mod.Baz} */
+var bb;
+>bb : number
+
+var bbb = new mod.Baz();
+>bbb : any
+>new mod.Baz() : any
+>mod.Baz : any
+>mod : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
+>Baz : any
+
+=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
+declare function require(name: string): any;
+>require : (name: string) => any
+>name : string
+
+declare var module: { exports: any};
+>module : { exports: any; }
+>exports : any
+
+declare var exports: any;
+>exports : any
+
+=== tests/cases/conformance/jsdoc/mod1.js ===
+/// <reference path="./commonjs.d.ts"/>
+
+// error
+
+/** @typedef {number} Foo */
+class Foo { } // should error
+>Foo : Foo
+
+/** @typedef {number} Bar */
+exports.Bar = class { }
+>exports.Bar = class { } : typeof Bar
+>exports.Bar : typeof Bar
+>exports : typeof import("tests/cases/conformance/jsdoc/mod1")
+>Bar : typeof Bar
+>class { } : typeof Bar
+
+/** @typedef {number} Baz */
+module.exports = {
+>module.exports = {    Baz: class { }} : { [x: string]: any; Baz: typeof Baz; }
+>module.exports : any
+>module : { exports: any; }
+>exports : any
+>{    Baz: class { }} : { [x: string]: any; Baz: typeof Baz; }
+
+    Baz: class { }
+>Baz : typeof Baz
+>class { } : typeof Baz
+}
+
+// ok
+
+/** @typedef {number} Qux */
+var Qux = 2;
+>Qux : number
+>2 : 2
+
+/** @typedef {number} Quid */
+exports.Quid = 2;
+>exports.Quid = 2 : 2
+>exports.Quid : any
+>exports : typeof import("tests/cases/conformance/jsdoc/mod1")
+>Quid : any
+>2 : 2
+
+/** @typedef {number} Quack */
+module.exports = {
+>module.exports = {    Quack: 2} : { [x: string]: any; Quack: number; }
+>module.exports : any
+>module : { exports: any; }
+>exports : any
+>{    Quack: 2} : { [x: string]: any; Quack: number; }
+
+    Quack: 2
+>Quack : number
+>2 : 2
+}
+
diff --git a/tests/cases/conformance/jsdoc/typedefCrossModule2.ts b/tests/cases/conformance/jsdoc/typedefCrossModule2.ts
new file mode 100644
index 0000000000000..99398f4995623
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/typedefCrossModule2.ts
@@ -0,0 +1,45 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: commonjs.d.ts
+declare function require(name: string): any;
+declare var module: { exports: any};
+declare var exports: any;
+
+// @Filename: mod1.js
+/// <reference path="./commonjs.d.ts"/>
+
+// error
+
+/** @typedef {number} Foo */
+class Foo { } // should error
+
+/** @typedef {number} Bar */
+exports.Bar = class { }
+
+/** @typedef {number} Baz */
+module.exports = {
+    Baz: class { }
+}
+
+// ok
+
+/** @typedef {number} Qux */
+var Qux = 2;
+
+/** @typedef {number} Quid */
+exports.Quid = 2;
+
+/** @typedef {number} Quack */
+module.exports = {
+    Quack: 2
+}
+
+// @Filename: use.js
+
+var mod = require('./mod1.js');
+/** @type {import("./mod1.js").Baz} */
+var b;
+/** @type {mod.Baz} */
+var bb;
+var bbb = new mod.Baz();

From 0f797a1e4e4680c8980ebdcd4a7be3916706dce4 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Mon, 30 Apr 2018 12:24:40 -0700
Subject: [PATCH 4/5] Fix class type reference resolution+update baselines

---
 src/compiler/checker.ts                       | 31 ++++++++++++++-----
 .../fourslash/findAllRefsClassExpression2.ts  |  4 +--
 ...refactorConvertToEs6Module_export_named.ts |  4 ++-
 ...ToEs6Module_export_namedClassExpression.ts | 10 ++++--
 ...vertToEs6Module_expressionToDeclaration.ts |  5 ++-
 5 files changed, 40 insertions(+), 14 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index afd5ba66c24e5..5f8d071f93fe3 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7562,23 +7562,38 @@ namespace ts {
                 return unknownType;
             }
 
-            // A jsdoc TypeReference may have resolved to a value (as opposed to a type). If
-            // the symbol is a constructor function, return the inferred class type; otherwise,
-            // the type of this reference is just the type of the value we resolved to.
+            const jsdocType = getJSDocTypeReference(node, symbol, typeArguments);
+            if (jsdocType) {
+                return jsdocType;
+            }
+
+            // Resolve the type reference as a Type for the purpose of reporting errors.
+            resolveTypeReferenceName(getTypeReferenceName(node), SymbolFlags.Type);
+            return getTypeOfSymbol(symbol);
+        }
+
+        /**
+         * A jsdoc TypeReference may have resolved to a value (as opposed to a type). If
+         * the symbol is a constructor function, return the inferred class type; otherwise,
+         * the type of this reference is just the type of the value we resolved to.
+         */
+        function getJSDocTypeReference(node: NodeWithTypeArguments, symbol: Symbol, typeArguments: Type[]): Type | undefined {
             const assignedType = getAssignedClassType(symbol);
             const valueType = getTypeOfSymbol(symbol);
-            const referenceType = valueType.symbol && !isInferredClassType(valueType) && getTypeReferenceTypeWorker(node, valueType.symbol, typeArguments);
+            const referenceType = valueType.symbol && valueType.symbol !== symbol && !isInferredClassType(valueType) && getTypeReferenceTypeWorker(node, valueType.symbol, typeArguments);
             if (referenceType || assignedType) {
                 return referenceType && assignedType ? getIntersectionType([assignedType, referenceType]) : referenceType || assignedType;
             }
-
-            // Resolve the type reference as a Type for the purpose of reporting errors.
-            resolveTypeReferenceName(getTypeReferenceName(node), SymbolFlags.Type);
-            return valueType;
         }
 
         function getTypeReferenceTypeWorker(node: NodeWithTypeArguments, symbol: Symbol, typeArguments: Type[]): Type | undefined {
             if (symbol.flags & (SymbolFlags.Class | SymbolFlags.Interface)) {
+                if (symbol.valueDeclaration && isBinaryExpression(symbol.valueDeclaration.parent)) {
+                    const jsdocType = getJSDocTypeReference(node, symbol, typeArguments);
+                    if (jsdocType) {
+                        return jsdocType;
+                    }
+                }
                 return getTypeFromClassOrInterfaceReference(node, symbol, typeArguments);
             }
 
diff --git a/tests/cases/fourslash/findAllRefsClassExpression2.ts b/tests/cases/fourslash/findAllRefsClassExpression2.ts
index f25e64a2c68e8..1214e3f7c8856 100644
--- a/tests/cases/fourslash/findAllRefsClassExpression2.ts
+++ b/tests/cases/fourslash/findAllRefsClassExpression2.ts
@@ -10,7 +10,7 @@
 ////[|A|];
 
 const [r0, r1, r2] = test.ranges();
-const defs = { definition: "(property) A: typeof A", ranges: [r0] };
-const imports = { definition: "(alias) (property) A: typeof A\nimport A", ranges: [r1, r2] };
+const defs = { definition: "class A\n(property) A: typeof A", ranges: [r0] };
+const imports = { definition: "(alias) class A\n(alias) (property) A: typeof A\nimport A", ranges: [r1, r2] };
 verify.referenceGroups([r0], [defs, imports]);
 verify.referenceGroups([r1, r2], [imports, defs]);
diff --git a/tests/cases/fourslash/refactorConvertToEs6Module_export_named.ts b/tests/cases/fourslash/refactorConvertToEs6Module_export_named.ts
index e7ee290858038..f8eba2b02134b 100644
--- a/tests/cases/fourslash/refactorConvertToEs6Module_export_named.ts
+++ b/tests/cases/fourslash/refactorConvertToEs6Module_export_named.ts
@@ -21,7 +21,9 @@ verify.codeFix({
     description: "Convert to ES6 module",
     newFileContent:
 `export function f() {}
-export class C {}
+const _C = class {
+};
+export { _C as C };
 export const x = 0;
 export function a1() {}
 export function a2() { return 0; }
diff --git a/tests/cases/fourslash/refactorConvertToEs6Module_export_namedClassExpression.ts b/tests/cases/fourslash/refactorConvertToEs6Module_export_namedClassExpression.ts
index e1cb86e8d682e..47b8a5e0b32cf 100644
--- a/tests/cases/fourslash/refactorConvertToEs6Module_export_namedClassExpression.ts
+++ b/tests/cases/fourslash/refactorConvertToEs6Module_export_namedClassExpression.ts
@@ -10,6 +10,12 @@
 verify.codeFix({
     description: "Convert to ES6 module",
     newFileContent:
-`export const C = class E { static instance = new E(); }
-export class D { static instance = new D(); }`,
+`const _C = class E {
+    static instance = new E();
+};
+export { _C as C };
+const _D = class D {
+    static instance = new D();
+};
+export { _D as D };`,
 });
diff --git a/tests/cases/fourslash/refactorConvertToEs6Module_expressionToDeclaration.ts b/tests/cases/fourslash/refactorConvertToEs6Module_expressionToDeclaration.ts
index 47ff26f459ed2..b360334767f9e 100644
--- a/tests/cases/fourslash/refactorConvertToEs6Module_expressionToDeclaration.ts
+++ b/tests/cases/fourslash/refactorConvertToEs6Module_expressionToDeclaration.ts
@@ -11,5 +11,8 @@ verify.codeFix({
     description: "Convert to ES6 module",
     newFileContent:
 `export async function* f(p) { p; }
-export class C extends D { m() {} }`,
+const _C = class C extends D {
+    m() { }
+};
+export { _C as C };`,
 });

From f733b21a460e7c29042f6f266d046fe76dba59ae Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Mon, 30 Apr 2018 13:09:15 -0700
Subject: [PATCH 5/5] Move to a type-based check for duplicate identifiers

---
 src/compiler/checker.ts                       | 29 ++++++++-----
 .../reference/typedefCrossModule2.errors.txt  | 32 +++++++-------
 .../reference/typedefCrossModule2.symbols     | 43 ++++++-------------
 .../reference/typedefCrossModule2.types       | 20 ++-------
 .../reference/typedefCrossModule3.errors.txt  | 18 ++++++++
 .../reference/typedefCrossModule3.symbols     | 16 +++++++
 .../reference/typedefCrossModule3.types       | 21 +++++++++
 .../reference/typedefCrossModule4.errors.txt  | 17 ++++++++
 .../reference/typedefCrossModule4.symbols     | 12 ++++++
 .../reference/typedefCrossModule4.types       | 15 +++++++
 .../conformance/jsdoc/typedefCrossModule2.ts  |  6 ---
 .../conformance/jsdoc/typedefCrossModule3.ts  | 10 +++++
 .../conformance/jsdoc/typedefCrossModule4.ts  |  9 ++++
 13 files changed, 170 insertions(+), 78 deletions(-)
 create mode 100644 tests/baselines/reference/typedefCrossModule3.errors.txt
 create mode 100644 tests/baselines/reference/typedefCrossModule3.symbols
 create mode 100644 tests/baselines/reference/typedefCrossModule3.types
 create mode 100644 tests/baselines/reference/typedefCrossModule4.errors.txt
 create mode 100644 tests/baselines/reference/typedefCrossModule4.symbols
 create mode 100644 tests/baselines/reference/typedefCrossModule4.types
 create mode 100644 tests/cases/conformance/jsdoc/typedefCrossModule3.ts
 create mode 100644 tests/cases/conformance/jsdoc/typedefCrossModule4.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 5f8d071f93fe3..3b55883f1317f 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -19930,6 +19930,7 @@ namespace ts {
                         getUnionType([removeDefinitelyFalsyTypes(leftType), rightType], UnionReduction.Subtype) :
                         leftType;
                 case SyntaxKind.EqualsToken:
+                    checkSpecialAssignment(left, right);
                     checkAssignmentOperator(rightType);
                     return getRegularTypeOfObjectLiteral(rightType);
                 case SyntaxKind.CommaToken:
@@ -19939,6 +19940,24 @@ namespace ts {
                     return rightType;
             }
 
+            function checkSpecialAssignment(left: Node, right: Expression) {
+                const special = getSpecialPropertyAssignmentKind(left.parent as BinaryExpression);
+                if (special === SpecialPropertyAssignmentKind.ModuleExports) {
+                    const rightType = checkExpression(right, checkMode);
+                    for (const prop of getPropertiesOfObjectType(rightType)) {
+                        const propType = getTypeOfSymbol(prop);
+                        if (propType.symbol && propType.symbol.flags & SymbolFlags.Class) {
+                            const name = prop.escapedName;
+                            const symbol = resolveName(prop.valueDeclaration, name, SymbolFlags.Type, undefined, name, /*isUse*/ false);
+                            if (symbol) {
+                                grammarErrorOnNode(symbol.declarations[0], Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(name));
+                                return grammarErrorOnNode(prop.valueDeclaration, Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(name));
+                            }
+                        }
+                    }
+                }
+            }
+
             function isEvalNode(node: Expression) {
                 return node.kind === SyntaxKind.Identifier && (node as Identifier).escapedText === "eval";
             }
@@ -27235,16 +27254,6 @@ namespace ts {
                 let currentKind: Flags;
                 switch (prop.kind) {
                     case SyntaxKind.PropertyAssignment:
-                        if (isClassExpression(prop.initializer)) {
-                            const n = prop.name;
-                            const sn = getTextOfPropertyName(n);
-                            const symbol = resolveName(n, sn, SymbolFlags.Type, undefined, sn, /*isUse*/ false);
-                            if (symbol) {
-                                grammarErrorOnNode(symbol.declarations[0], Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(sn));
-                                return grammarErrorOnNode(n, Diagnostics.Duplicate_identifier_0, unescapeLeadingUnderscores(sn));
-                            }
-                        }
-                       // falls through
                     case SyntaxKind.ShorthandPropertyAssignment:
                         // Grammar checking for computedPropertyName and shorthandPropertyAssignment
                         checkGrammarForInvalidQuestionMark(prop.questionToken, Diagnostics.An_object_member_cannot_be_declared_optional);
diff --git a/tests/baselines/reference/typedefCrossModule2.errors.txt b/tests/baselines/reference/typedefCrossModule2.errors.txt
index 1d7fbb3bde265..04d28448e5795 100644
--- a/tests/baselines/reference/typedefCrossModule2.errors.txt
+++ b/tests/baselines/reference/typedefCrossModule2.errors.txt
@@ -1,27 +1,25 @@
-tests/cases/conformance/jsdoc/mod1.js(5,23): error TS2300: Duplicate identifier 'Foo'.
-tests/cases/conformance/jsdoc/mod1.js(6,7): error TS2300: Duplicate identifier 'Foo'.
-tests/cases/conformance/jsdoc/mod1.js(8,23): error TS2300: Duplicate identifier 'Bar'.
-tests/cases/conformance/jsdoc/mod1.js(9,9): error TS2300: Duplicate identifier 'Bar'.
+tests/cases/conformance/jsdoc/mod1.js(3,23): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod1.js(4,7): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod1.js(6,23): error TS2300: Duplicate identifier 'Bar'.
+tests/cases/conformance/jsdoc/mod1.js(7,9): error TS2300: Duplicate identifier 'Bar'.
+tests/cases/conformance/jsdoc/mod1.js(9,5): error TS2300: Duplicate identifier 'Baz'.
+tests/cases/conformance/jsdoc/mod1.js(10,1): error TS2304: Cannot find name 'module'.
 tests/cases/conformance/jsdoc/mod1.js(11,5): error TS2300: Duplicate identifier 'Baz'.
-tests/cases/conformance/jsdoc/mod1.js(13,5): error TS2300: Duplicate identifier 'Baz'.
+tests/cases/conformance/jsdoc/mod1.js(23,1): error TS2304: Cannot find name 'module'.
+tests/cases/conformance/jsdoc/use.js(1,11): error TS2304: Cannot find name 'require'.
 
 
-==== tests/cases/conformance/jsdoc/use.js (0 errors) ====
+==== tests/cases/conformance/jsdoc/use.js (1 errors) ====
     var mod = require('./mod1.js');
+              ~~~~~~~
+!!! error TS2304: Cannot find name 'require'.
     /** @type {import("./mod1.js").Baz} */
     var b;
     /** @type {mod.Baz} */
     var bb;
     var bbb = new mod.Baz();
     
-==== tests/cases/conformance/jsdoc/commonjs.d.ts (0 errors) ====
-    declare function require(name: string): any;
-    declare var module: { exports: any};
-    declare var exports: any;
-    
-==== tests/cases/conformance/jsdoc/mod1.js (6 errors) ====
-    /// <reference path="./commonjs.d.ts"/>
-    
+==== tests/cases/conformance/jsdoc/mod1.js (8 errors) ====
     // error
     
     /** @typedef {number} Foo */
@@ -42,8 +40,10 @@ tests/cases/conformance/jsdoc/mod1.js(13,5): error TS2300: Duplicate identifier
         ~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2300: Duplicate identifier 'Baz'.
     module.exports = {
+    ~~~~~~
+!!! error TS2304: Cannot find name 'module'.
         Baz: class { }
-        ~~~
+        ~~~~~~~~~~~~~~
 !!! error TS2300: Duplicate identifier 'Baz'.
     }
     
@@ -57,6 +57,8 @@ tests/cases/conformance/jsdoc/mod1.js(13,5): error TS2300: Duplicate identifier
     
     /** @typedef {number} Quack */
     module.exports = {
+    ~~~~~~
+!!! error TS2304: Cannot find name 'module'.
         Quack: 2
     }
     
\ No newline at end of file
diff --git a/tests/baselines/reference/typedefCrossModule2.symbols b/tests/baselines/reference/typedefCrossModule2.symbols
index 5c51828176b97..01afe2b9bdb75 100644
--- a/tests/baselines/reference/typedefCrossModule2.symbols
+++ b/tests/baselines/reference/typedefCrossModule2.symbols
@@ -1,7 +1,6 @@
 === tests/cases/conformance/jsdoc/use.js ===
 var mod = require('./mod1.js');
 >mod : Symbol(mod, Decl(use.js, 0, 3))
->require : Symbol(require, Decl(commonjs.d.ts, 0, 0))
 >'./mod1.js' : Symbol("tests/cases/conformance/jsdoc/mod1", Decl(mod1.js, 0, 0))
 
 /** @type {import("./mod1.js").Baz} */
@@ -16,21 +15,7 @@ var bbb = new mod.Baz();
 >bbb : Symbol(bbb, Decl(use.js, 5, 3))
 >mod : Symbol(mod, Decl(use.js, 0, 3))
 
-=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
-declare function require(name: string): any;
->require : Symbol(require, Decl(commonjs.d.ts, 0, 0))
->name : Symbol(name, Decl(commonjs.d.ts, 0, 25))
-
-declare var module: { exports: any};
->module : Symbol(module, Decl(commonjs.d.ts, 1, 11))
->exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
-
-declare var exports: any;
->exports : Symbol(exports, Decl(commonjs.d.ts, 2, 11))
-
 === tests/cases/conformance/jsdoc/mod1.js ===
-/// <reference path="./commonjs.d.ts"/>
-
 // error
 
 /** @typedef {number} Foo */
@@ -39,39 +24,37 @@ class Foo { } // should error
 
 /** @typedef {number} Bar */
 exports.Bar = class { }
->exports.Bar : Symbol(Bar, Decl(mod1.js, 5, 13))
->exports : Symbol(Bar, Decl(mod1.js, 5, 13))
->Bar : Symbol(Bar, Decl(mod1.js, 5, 13))
+>exports.Bar : Symbol(Bar, Decl(mod1.js, 3, 13))
+>exports : Symbol(Bar, Decl(mod1.js, 3, 13))
+>Bar : Symbol(Bar, Decl(mod1.js, 3, 13))
 
 /** @typedef {number} Baz */
 module.exports = {
->module.exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
->module : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
->exports : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+>module : Symbol(export=, Decl(mod1.js, 6, 23), Decl(mod1.js, 19, 17))
+>exports : Symbol(export=, Decl(mod1.js, 6, 23), Decl(mod1.js, 19, 17))
 
     Baz: class { }
->Baz : Symbol(Baz, Decl(mod1.js, 11, 18))
+>Baz : Symbol(Baz, Decl(mod1.js, 9, 18))
 }
 
 // ok
 
 /** @typedef {number} Qux */
 var Qux = 2;
->Qux : Symbol(Qux, Decl(mod1.js, 18, 3), Decl(mod1.js, 17, 4))
+>Qux : Symbol(Qux, Decl(mod1.js, 16, 3), Decl(mod1.js, 15, 4))
 
 /** @typedef {number} Quid */
 exports.Quid = 2;
->exports.Quid : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
->exports : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
->Quid : Symbol(Quid, Decl(mod1.js, 18, 12), Decl(mod1.js, 20, 4))
+>exports.Quid : Symbol(Quid, Decl(mod1.js, 16, 12), Decl(mod1.js, 18, 4))
+>exports : Symbol(Quid, Decl(mod1.js, 16, 12), Decl(mod1.js, 18, 4))
+>Quid : Symbol(Quid, Decl(mod1.js, 16, 12), Decl(mod1.js, 18, 4))
 
 /** @typedef {number} Quack */
 module.exports = {
->module.exports : Symbol(exports, Decl(commonjs.d.ts, 1, 21))
->module : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
->exports : Symbol(export=, Decl(mod1.js, 8, 23), Decl(mod1.js, 21, 17))
+>module : Symbol(export=, Decl(mod1.js, 6, 23), Decl(mod1.js, 19, 17))
+>exports : Symbol(export=, Decl(mod1.js, 6, 23), Decl(mod1.js, 19, 17))
 
     Quack: 2
->Quack : Symbol(Quack, Decl(mod1.js, 24, 18))
+>Quack : Symbol(Quack, Decl(mod1.js, 22, 18))
 }
 
diff --git a/tests/baselines/reference/typedefCrossModule2.types b/tests/baselines/reference/typedefCrossModule2.types
index 2cf4314c33599..67e4b7a4e890e 100644
--- a/tests/baselines/reference/typedefCrossModule2.types
+++ b/tests/baselines/reference/typedefCrossModule2.types
@@ -2,7 +2,7 @@
 var mod = require('./mod1.js');
 >mod : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
 >require('./mod1.js') : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
->require : (name: string) => any
+>require : any
 >'./mod1.js' : "./mod1.js"
 
 /** @type {import("./mod1.js").Baz} */
@@ -20,21 +20,7 @@ var bbb = new mod.Baz();
 >mod : { [x: string]: any; Baz: any; Bar: typeof Bar; Quid: any; } | { [x: string]: any; Quack: any; Bar: typeof Bar; Quid: any; }
 >Baz : any
 
-=== tests/cases/conformance/jsdoc/commonjs.d.ts ===
-declare function require(name: string): any;
->require : (name: string) => any
->name : string
-
-declare var module: { exports: any};
->module : { exports: any; }
->exports : any
-
-declare var exports: any;
->exports : any
-
 === tests/cases/conformance/jsdoc/mod1.js ===
-/// <reference path="./commonjs.d.ts"/>
-
 // error
 
 /** @typedef {number} Foo */
@@ -53,7 +39,7 @@ exports.Bar = class { }
 module.exports = {
 >module.exports = {    Baz: class { }} : { [x: string]: any; Baz: typeof Baz; }
 >module.exports : any
->module : { exports: any; }
+>module : any
 >exports : any
 >{    Baz: class { }} : { [x: string]: any; Baz: typeof Baz; }
 
@@ -81,7 +67,7 @@ exports.Quid = 2;
 module.exports = {
 >module.exports = {    Quack: 2} : { [x: string]: any; Quack: number; }
 >module.exports : any
->module : { exports: any; }
+>module : any
 >exports : any
 >{    Quack: 2} : { [x: string]: any; Quack: number; }
 
diff --git a/tests/baselines/reference/typedefCrossModule3.errors.txt b/tests/baselines/reference/typedefCrossModule3.errors.txt
new file mode 100644
index 0000000000000..5309528fb4e6c
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule3.errors.txt
@@ -0,0 +1,18 @@
+tests/cases/conformance/jsdoc/mod2.js(1,5): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod2.js(3,1): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod2.js(4,1): error TS2304: Cannot find name 'module'.
+
+
+==== tests/cases/conformance/jsdoc/mod2.js (3 errors) ====
+    /** @typedef {number} Foo */
+        ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    const ns = {};
+    ns.Foo = class {}
+    ~~~~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    module.exports = ns;
+    ~~~~~~
+!!! error TS2304: Cannot find name 'module'.
+    
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/typedefCrossModule3.symbols b/tests/baselines/reference/typedefCrossModule3.symbols
new file mode 100644
index 0000000000000..3e1c8a55535df
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule3.symbols
@@ -0,0 +1,16 @@
+=== tests/cases/conformance/jsdoc/mod2.js ===
+/** @typedef {number} Foo */
+const ns = {};
+>ns : Symbol(ns, Decl(mod2.js, 1, 5), Decl(mod2.js, 1, 14))
+
+ns.Foo = class {}
+>ns.Foo : Symbol(Foo, Decl(mod2.js, 1, 14))
+>ns : Symbol(ns, Decl(mod2.js, 1, 5), Decl(mod2.js, 1, 14))
+>Foo : Symbol(Foo, Decl(mod2.js, 1, 14))
+
+module.exports = ns;
+>module : Symbol(export=, Decl(mod2.js, 2, 17))
+>exports : Symbol(export=, Decl(mod2.js, 2, 17))
+>ns : Symbol(ns, Decl(mod2.js, 1, 5), Decl(mod2.js, 1, 14))
+
+
diff --git a/tests/baselines/reference/typedefCrossModule3.types b/tests/baselines/reference/typedefCrossModule3.types
new file mode 100644
index 0000000000000..9d3767dcbbaba
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule3.types
@@ -0,0 +1,21 @@
+=== tests/cases/conformance/jsdoc/mod2.js ===
+/** @typedef {number} Foo */
+const ns = {};
+>ns : { [x: string]: any; Foo: typeof Foo; }
+>{} : { [x: string]: any; Foo: typeof Foo; }
+
+ns.Foo = class {}
+>ns.Foo = class {} : typeof Foo
+>ns.Foo : typeof Foo
+>ns : { [x: string]: any; Foo: typeof Foo; }
+>Foo : typeof Foo
+>class {} : typeof Foo
+
+module.exports = ns;
+>module.exports = ns : { [x: string]: any; Foo: typeof Foo; }
+>module.exports : any
+>module : any
+>exports : any
+>ns : { [x: string]: any; Foo: typeof Foo; }
+
+
diff --git a/tests/baselines/reference/typedefCrossModule4.errors.txt b/tests/baselines/reference/typedefCrossModule4.errors.txt
new file mode 100644
index 0000000000000..5dcd9ac017bfe
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule4.errors.txt
@@ -0,0 +1,17 @@
+tests/cases/conformance/jsdoc/mod3.js(1,5): error TS2300: Duplicate identifier 'Foo'.
+tests/cases/conformance/jsdoc/mod3.js(3,1): error TS2304: Cannot find name 'module'.
+tests/cases/conformance/jsdoc/mod3.js(3,20): error TS2300: Duplicate identifier 'Foo'.
+
+
+==== tests/cases/conformance/jsdoc/mod3.js (3 errors) ====
+    /** @typedef {number} Foo */
+        ~~~~~~~~~~~~~~~~~~~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    class Bar { }
+    module.exports = { Foo: Bar };
+    ~~~~~~
+!!! error TS2304: Cannot find name 'module'.
+                       ~~~~~~~~
+!!! error TS2300: Duplicate identifier 'Foo'.
+    
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/typedefCrossModule4.symbols b/tests/baselines/reference/typedefCrossModule4.symbols
new file mode 100644
index 0000000000000..aa478df301a9c
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule4.symbols
@@ -0,0 +1,12 @@
+=== tests/cases/conformance/jsdoc/mod3.js ===
+/** @typedef {number} Foo */
+class Bar { }
+>Bar : Symbol(Bar, Decl(mod3.js, 0, 0))
+
+module.exports = { Foo: Bar };
+>module : Symbol(export=, Decl(mod3.js, 1, 13))
+>exports : Symbol(export=, Decl(mod3.js, 1, 13))
+>Foo : Symbol(Foo, Decl(mod3.js, 2, 18))
+>Bar : Symbol(Bar, Decl(mod3.js, 0, 0))
+
+
diff --git a/tests/baselines/reference/typedefCrossModule4.types b/tests/baselines/reference/typedefCrossModule4.types
new file mode 100644
index 0000000000000..a0d14942ef3b5
--- /dev/null
+++ b/tests/baselines/reference/typedefCrossModule4.types
@@ -0,0 +1,15 @@
+=== tests/cases/conformance/jsdoc/mod3.js ===
+/** @typedef {number} Foo */
+class Bar { }
+>Bar : Bar
+
+module.exports = { Foo: Bar };
+>module.exports = { Foo: Bar } : { [x: string]: any; Foo: typeof Bar; }
+>module.exports : any
+>module : any
+>exports : any
+>{ Foo: Bar } : { [x: string]: any; Foo: typeof Bar; }
+>Foo : typeof Bar
+>Bar : typeof Bar
+
+
diff --git a/tests/cases/conformance/jsdoc/typedefCrossModule2.ts b/tests/cases/conformance/jsdoc/typedefCrossModule2.ts
index 99398f4995623..6bb00957ef396 100644
--- a/tests/cases/conformance/jsdoc/typedefCrossModule2.ts
+++ b/tests/cases/conformance/jsdoc/typedefCrossModule2.ts
@@ -1,13 +1,7 @@
 // @noEmit: true
 // @allowJs: true
 // @checkJs: true
-// @Filename: commonjs.d.ts
-declare function require(name: string): any;
-declare var module: { exports: any};
-declare var exports: any;
-
 // @Filename: mod1.js
-/// <reference path="./commonjs.d.ts"/>
 
 // error
 
diff --git a/tests/cases/conformance/jsdoc/typedefCrossModule3.ts b/tests/cases/conformance/jsdoc/typedefCrossModule3.ts
new file mode 100644
index 0000000000000..d6005b541dcb7
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/typedefCrossModule3.ts
@@ -0,0 +1,10 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: mod2.js
+
+/** @typedef {number} Foo */
+const ns = {};
+ns.Foo = class {}
+module.exports = ns;
+
diff --git a/tests/cases/conformance/jsdoc/typedefCrossModule4.ts b/tests/cases/conformance/jsdoc/typedefCrossModule4.ts
new file mode 100644
index 0000000000000..09d27246c7c8f
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/typedefCrossModule4.ts
@@ -0,0 +1,9 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: mod3.js
+
+/** @typedef {number} Foo */
+class Bar { }
+module.exports = { Foo: Bar };
+