Weak type errors for primitives

src/compiler/checker.ts

@@ -14214,9 +14214,13 @@ namespace ts {
 
         /**
          * Check if a property with the given name is known anywhere in the given type. In an object type, a property
-         * is considered known if the object type is empty and the check is for assignability, if the object type has
-         * index signatures, or if the property is actually declared in the object type. In a union or intersection
-         * type, a property is considered known if it is known in any constituent type.
+         * is considered known if
+         * 1. the object type is empty and the check is for assignability, or
+         * 2. if the object type has index signatures, or
+         * 3. if the property is actually declared in the object type
+         *    (this means that 'toString', for example, is not usually a known property).
+         * 4. In a union or intersection type,
+         *    a property is considered known if it is known in any constituent type.
          * @param targetType a type to search a given name in
          * @param name a property name to search
          * @param isComparingJsxAttributes a boolean flag indicating whether we are searching in JsxAttributesType
@@ -14226,7 +14230,7 @@ namespace ts {
                 const resolved = resolveStructuredTypeMembers(<ObjectType>targetType);
                 if (resolved.stringIndexInfo ||
                     resolved.numberIndexInfo && isNumericLiteralName(name) ||
-                    getPropertyOfType(targetType, name) ||
+                    getPropertyOfObjectType(targetType, name) ||
                     isComparingJsxAttributes && !isUnhyphenatedJsxName(name)) {
                     // For JSXAttributes, if the attribute has a hyphenated name, consider that the attribute to be known.
                     return true;

tests/baselines/reference/generatorTypeCheck63.errors.txt

@@ -1,11 +1,12 @@
-tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(24,14): error TS2322: Type '(a: State | 1) => IterableIterator<State | 1>' is not assignable to type 'Strategy<State>'.
-  Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<State>'.
-    Type 'State | 1' is not assignable to type 'State'.
-      Type '1' is not assignable to type 'State'.
+tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(24,61): error TS2345: Argument of type '(state: State) => IterableIterator<State | 1>' is not assignable to parameter of type '(a: StrategicState) => IterableIterator<StrategicState>'.
+  Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<StrategicState>'.
+    Type 'State | 1' is not assignable to type 'StrategicState'.
+      Type '1' has no properties in common with type 'StrategicState'.
 tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(29,70): error TS7025: Generator implicitly has type 'IterableIterator<any>' because it does not yield any values. Consider supplying a return type.
 tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(32,42): error TS2453: The type argument for type parameter 'T' cannot be inferred from the usage. Consider specifying the type arguments explicitly.
   Type argument candidate 'State' is not a valid type argument because it is not a supertype of candidate '1'.
-tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(36,14): error TS2322: Type '(a: State | 1) => IterableIterator<State | 1>' is not assignable to type 'Strategy<State>'.
+tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(36,62): error TS2345: Argument of type '(state: State) => IterableIterator<State | 1>' is not assignable to parameter of type '(a: StrategicState) => IterableIterator<StrategicState>'.
+  Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<StrategicState>'.
 
 
 ==== tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts (4 errors) ====
@@ -33,11 +34,11 @@ tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(36,14): err
     }
 
     export const Nothing: Strategy<State> = strategy("Nothing", function* (state: State) {
-                 ~~~~~~~
-!!! error TS2322: Type '(a: State | 1) => IterableIterator<State | 1>' is not assignable to type 'Strategy<State>'.
-!!! error TS2322:   Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<State>'.
-!!! error TS2322:     Type 'State | 1' is not assignable to type 'State'.
-!!! error TS2322:       Type '1' is not assignable to type 'State'.
+                                                                ~~~~~~~~
+!!! error TS2345: Argument of type '(state: State) => IterableIterator<State | 1>' is not assignable to parameter of type '(a: StrategicState) => IterableIterator<StrategicState>'.
+!!! error TS2345:   Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<StrategicState>'.
+!!! error TS2345:     Type 'State | 1' is not assignable to type 'StrategicState'.
+!!! error TS2345:       Type '1' has no properties in common with type 'StrategicState'.
         yield 1;
         return state;
     });
@@ -55,8 +56,9 @@ tests/cases/conformance/es6/yieldExpressions/generatorTypeCheck63.ts(36,14): err
     });
 
     export const Nothing3: Strategy<State> = strategy("Nothing", function* (state: State) {
-                 ~~~~~~~~
-!!! error TS2322: Type '(a: State | 1) => IterableIterator<State | 1>' is not assignable to type 'Strategy<State>'.
+                                                                 ~~~~~~~~
+!!! error TS2345: Argument of type '(state: State) => IterableIterator<State | 1>' is not assignable to parameter of type '(a: StrategicState) => IterableIterator<StrategicState>'.
+!!! error TS2345:   Type 'IterableIterator<State | 1>' is not assignable to type 'IterableIterator<StrategicState>'.
         yield state;
         return 1;
     });

tests/baselines/reference/objectLiteralFunctionArgContextualTyping2.errors.txt

@@ -4,12 +4,12 @@ tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(9,4): error TS
   Property 'doStuff' is missing in type '{ value: string; }'.
 tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(10,17): error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I2'.
   Object literal may only specify known properties, and 'what' does not exist in type 'I2'.
-tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(11,4): error TS2345: Argument of type '{ toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
-  Property 'value' is missing in type '{ toString: (s: any) => any; }'.
-tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(12,4): error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I2'.
-  Property 'value' is missing in type '{ toString: (s: string) => string; }'.
-tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(13,4): error TS2345: Argument of type '{ value: string; toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
-  Property 'doStuff' is missing in type '{ value: string; toString: (s: any) => any; }'.
+tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(11,6): error TS2345: Argument of type '{ toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
+  Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.
+tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(12,6): error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I2'.
+  Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.
+tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(13,17): error TS2345: Argument of type '{ value: string; toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
+  Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.
 
 
 ==== tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts (6 errors) ====
@@ -33,14 +33,14 @@ tests/cases/compiler/objectLiteralFunctionArgContextualTyping2.ts(13,4): error T
 !!! error TS2345: Argument of type '{ value: string; what: number; }' is not assignable to parameter of type 'I2'.
 !!! error TS2345:   Object literal may only specify known properties, and 'what' does not exist in type 'I2'.
     f2({ toString: (s) => s }) 
-       ~~~~~~~~~~~~~~~~~~~~~~
+         ~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
-!!! error TS2345:   Property 'value' is missing in type '{ toString: (s: any) => any; }'.
+!!! error TS2345:   Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.
     f2({ toString: (s: string) => s }) 
-       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+         ~~~~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ toString: (s: string) => string; }' is not assignable to parameter of type 'I2'.
-!!! error TS2345:   Property 'value' is missing in type '{ toString: (s: string) => string; }'.
+!!! error TS2345:   Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.
     f2({ value: '', toString: (s) => s.uhhh }) 
-       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+                    ~~~~~~~~~~~~~~~~~~~~~~~
 !!! error TS2345: Argument of type '{ value: string; toString: (s: any) => any; }' is not assignable to parameter of type 'I2'.
-!!! error TS2345:   Property 'doStuff' is missing in type '{ value: string; toString: (s: any) => any; }'.
+!!! error TS2345:   Object literal may only specify known properties, and 'toString' does not exist in type 'I2'.

tests/baselines/reference/tsxSpreadAttributesResolution1.js

@@ -7,11 +7,12 @@ class Poisoned extends React.Component<{}, {}> {
     }
 }
 
-const obj: Object = {};
+const obj = {};
 
 // OK
 let p = <Poisoned {...obj} />;
-let y = <Poisoned />;
+let y = <Poisoned />;
+
 
 //// [file.jsx]
 "use strict";

tests/baselines/reference/tsxSpreadAttributesResolution1.symbols

@@ -17,9 +17,8 @@ class Poisoned extends React.Component<{}, {}> {
     }
 }
 
-const obj: Object = {};
+const obj = {};
 >obj : Symbol(obj, Decl(file.tsx, 8, 5))
->Object : Symbol(Object, Decl(lib.d.ts, --, --), Decl(lib.d.ts, --, --))
 
 // OK
 let p = <Poisoned {...obj} />;

tests/baselines/reference/tsxSpreadAttributesResolution1.types

@@ -18,17 +18,16 @@ class Poisoned extends React.Component<{}, {}> {
     }
 }
 
-const obj: Object = {};
->obj : Object
->Object : Object
+const obj = {};
+>obj : {}
 >{} : {}
 
 // OK
 let p = <Poisoned {...obj} />;
 >p : JSX.Element
 ><Poisoned {...obj} /> : JSX.Element
 >Poisoned : typeof Poisoned
->obj : Object
+>obj : {}
 
 let y = <Poisoned />;
 >y : JSX.Element

tests/baselines/reference/weakType.errors.txt

@@ -1,11 +1,14 @@
-tests/cases/compiler/weakType.ts(31,18): error TS2559: Type '{ error?: number; }' has no properties in common with type 'ChangeOptions'.
-tests/cases/compiler/weakType.ts(56,5): error TS2322: Type '{ properties: { wrong: string; }; }' is not assignable to type 'Weak & Spoiler'.
+tests/cases/compiler/weakType.ts(16,13): error TS2559: Type '12' has no properties in common with type 'Settings'.
+tests/cases/compiler/weakType.ts(17,13): error TS2559: Type '"completely wrong"' has no properties in common with type 'Settings'.
+tests/cases/compiler/weakType.ts(18,13): error TS2559: Type 'false' has no properties in common with type 'Settings'.
+tests/cases/compiler/weakType.ts(35,18): error TS2559: Type '{ error?: number; }' has no properties in common with type 'ChangeOptions'.
+tests/cases/compiler/weakType.ts(60,5): error TS2322: Type '{ properties: { wrong: string; }; }' is not assignable to type 'Weak & Spoiler'.
   Type '{ properties: { wrong: string; }; }' is not assignable to type 'Weak'.
     Types of property 'properties' are incompatible.
       Type '{ wrong: string; }' has no properties in common with type '{ b?: number; }'.
 
 
-==== tests/cases/compiler/weakType.ts (2 errors) ====
+==== tests/cases/compiler/weakType.ts (5 errors) ====
     interface Settings {
         timeout?: number;
         onError?(): void;
@@ -16,10 +19,20 @@ tests/cases/compiler/weakType.ts(56,5): error TS2322: Type '{ properties: { wron
     }
 
     function doSomething(settings: Settings) { /* ... */ }
-
     // forgot to call `getDefaultSettings`
     // but it is not caught because we don't check for call signatures
     doSomething(getDefaultSettings);
+    // same for arrow expressions:
+    doSomething(() => { });
+    doSomething(12);
+                ~~
+!!! error TS2559: Type '12' has no properties in common with type 'Settings'.
+    doSomething('completely wrong');
+                ~~~~~~~~~~~~~~~~~~
+!!! error TS2559: Type '"completely wrong"' has no properties in common with type 'Settings'.
+    doSomething(false);
+                ~~~~~
+!!! error TS2559: Type 'false' has no properties in common with type 'Settings'.
 
     // this is an oddly popular way of defining settings
     // this example is from services/textChanges.ts

tests/baselines/reference/weakType.js

@@ -9,10 +9,14 @@ function getDefaultSettings() {
 }
 
 function doSomething(settings: Settings) { /* ... */ }
-
 // forgot to call `getDefaultSettings`
 // but it is not caught because we don't check for call signatures
 doSomething(getDefaultSettings);
+// same for arrow expressions:
+doSomething(() => { });
+doSomething(12);
+doSomething('completely wrong');
+doSomething(false);
 
 // this is an oddly popular way of defining settings
 // this example is from services/textChanges.ts
@@ -65,6 +69,11 @@ function doSomething(settings) { }
 // forgot to call `getDefaultSettings`
 // but it is not caught because we don't check for call signatures
 doSomething(getDefaultSettings);
+// same for arrow expressions:
+doSomething(function () { });
+doSomething(12);
+doSomething('completely wrong');
+doSomething(false);
 function del(options, error) {
     if (options === void 0) { options = {}; }
     if (error === void 0) { error = {}; }

tests/cases/compiler/weakType.ts

@@ -8,10 +8,14 @@ function getDefaultSettings() {
 }
 
 function doSomething(settings: Settings) { /* ... */ }
-
 // forgot to call `getDefaultSettings`
 // but it is not caught because we don't check for call signatures
 doSomething(getDefaultSettings);
+// same for arrow expressions:
+doSomething(() => { });
+doSomething(12);
+doSomething('completely wrong');
+doSomething(false);
 
 // this is an oddly popular way of defining settings
 // this example is from services/textChanges.ts

tests/cases/conformance/jsx/tsxSpreadAttributesResolution1.tsx

@@ -11,8 +11,8 @@ class Poisoned extends React.Component<{}, {}> {
     }
 }
 
-const obj: Object = {};
+const obj = {};
 
 // OK
 let p = <Poisoned {...obj} />;
-let y = <Poisoned />;
+let y = <Poisoned />;