Widen object literal this types (#32240)

src/compiler/checker.ts

@@ -18288,7 +18288,7 @@ namespace ts {
                     // There was no contextual ThisType<T> for the containing object literal, so the contextual type
                     // for 'this' is the non-null form of the contextual type for the containing object literal or
                     // the type of the object literal itself.
-                    return contextualType ? getNonNullableType(contextualType) : checkExpressionCached(containingLiteral);
+                    return getWidenedType(contextualType ? getNonNullableType(contextualType) : checkExpressionCached(containingLiteral));
                 }
                 // In an assignment of the form 'obj.xxx = function(...)' or 'obj[xxx] = function(...)', the
                 // contextual type for 'this' is 'obj'.
@@ -18305,7 +18305,7 @@ namespace ts {
                             }
                         }
 
-                        return checkExpressionCached(expression);
+                        return getWidenedType(checkExpressionCached(expression));
                     }
                 }
             }

tests/baselines/reference/noImplicitThisBigThis.types

@@ -11,21 +11,21 @@ function createObj() {
 >func1 : () => { func1(): any; func2(): any; func3(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; }; func2(): { func1(): any; func2(): any; func3(): any; }; func3(): { func1(): any; func2(): any; func3(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; }
 
         },
         func2() {
 >func2 : () => { func1(): any; func2(): any; func3(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; }; func2(): { func1(): any; func2(): any; func3(): any; }; func3(): { func1(): any; func2(): any; func3(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; }
 
         },
         func3() {
 >func3 : () => { func1(): any; func2(): any; func3(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; }; func2(): { func1(): any; func2(): any; func3(): any; }; func3(): { func1(): any; func2(): any; func3(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; }
         }
     };
 }
@@ -40,63 +40,63 @@ function createObjNoCrash() {
 >func1 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func2() {
 >func2 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func3() {
 >func3 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func4() {
 >func4 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func5() {
 >func5 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func6() {
 >func6 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func7() {
 >func7 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func8() {
 >func8 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
         },
         func9() {
 >func9 : () => { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
 
             return this;
->this : { func1(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func2(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func3(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func4(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func5(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func6(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func7(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func8(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; func9(): { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }; }
+>this : { func1(): any; func2(): any; func3(): any; func4(): any; func5(): any; func6(): any; func7(): any; func8(): any; func9(): any; }
         }
     };
 }

tests/baselines/reference/objectLiteralThisWidenedOnUse.errors.txt

@@ -0,0 +1,22 @@
+tests/cases/compiler/objectLiteralThisWidenedOnUse.ts(8,21): error TS2345: Argument of type '{ prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }' is not assignable to parameter of type 'Foo'.
+  Property 'bar' is missing in type '{ prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }' but required in type 'Foo'.
+
+
+==== tests/cases/compiler/objectLiteralThisWidenedOnUse.ts (1 errors) ====
+    interface Foo { bar: boolean; }
+    
+    var GlobalIns = {
+      prop1: 1,
+      prop2: 2,
+      prop3: 3,
+      test () {
+        this.accept_foo(this);
+                        ~~~~
+!!! error TS2345: Argument of type '{ prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }' is not assignable to parameter of type 'Foo'.
+!!! error TS2345:   Property 'bar' is missing in type '{ prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }' but required in type 'Foo'.
+!!! related TS2728 tests/cases/compiler/objectLiteralThisWidenedOnUse.ts:1:17: 'bar' is declared here.
+      },
+      accept_foo (foo: Foo): boolean {
+        return !!foo && !!foo.bar;
+      }
+    };

tests/baselines/reference/objectLiteralThisWidenedOnUse.js

@@ -0,0 +1,27 @@
+//// [objectLiteralThisWidenedOnUse.ts]
+interface Foo { bar: boolean; }
+
+var GlobalIns = {
+  prop1: 1,
+  prop2: 2,
+  prop3: 3,
+  test () {
+    this.accept_foo(this);
+  },
+  accept_foo (foo: Foo): boolean {
+    return !!foo && !!foo.bar;
+  }
+};
+
+//// [objectLiteralThisWidenedOnUse.js]
+var GlobalIns = {
+    prop1: 1,
+    prop2: 2,
+    prop3: 3,
+    test: function () {
+        this.accept_foo(this);
+    },
+    accept_foo: function (foo) {
+        return !!foo && !!foo.bar;
+    }
+};

tests/baselines/reference/objectLiteralThisWidenedOnUse.symbols

@@ -0,0 +1,39 @@
+=== tests/cases/compiler/objectLiteralThisWidenedOnUse.ts ===
+interface Foo { bar: boolean; }
+>Foo : Symbol(Foo, Decl(objectLiteralThisWidenedOnUse.ts, 0, 0))
+>bar : Symbol(Foo.bar, Decl(objectLiteralThisWidenedOnUse.ts, 0, 15))
+
+var GlobalIns = {
+>GlobalIns : Symbol(GlobalIns, Decl(objectLiteralThisWidenedOnUse.ts, 2, 3))
+
+  prop1: 1,
+>prop1 : Symbol(prop1, Decl(objectLiteralThisWidenedOnUse.ts, 2, 17))
+
+  prop2: 2,
+>prop2 : Symbol(prop2, Decl(objectLiteralThisWidenedOnUse.ts, 3, 11))
+
+  prop3: 3,
+>prop3 : Symbol(prop3, Decl(objectLiteralThisWidenedOnUse.ts, 4, 11))
+
+  test () {
+>test : Symbol(test, Decl(objectLiteralThisWidenedOnUse.ts, 5, 11))
+
+    this.accept_foo(this);
+>this.accept_foo : Symbol(accept_foo, Decl(objectLiteralThisWidenedOnUse.ts, 8, 4))
+>this : Symbol(GlobalIns, Decl(objectLiteralThisWidenedOnUse.ts, 2, 15))
+>accept_foo : Symbol(accept_foo, Decl(objectLiteralThisWidenedOnUse.ts, 8, 4))
+>this : Symbol(GlobalIns, Decl(objectLiteralThisWidenedOnUse.ts, 2, 15))
+
+  },
+  accept_foo (foo: Foo): boolean {
+>accept_foo : Symbol(accept_foo, Decl(objectLiteralThisWidenedOnUse.ts, 8, 4))
+>foo : Symbol(foo, Decl(objectLiteralThisWidenedOnUse.ts, 9, 14))
+>Foo : Symbol(Foo, Decl(objectLiteralThisWidenedOnUse.ts, 0, 0))
+
+    return !!foo && !!foo.bar;
+>foo : Symbol(foo, Decl(objectLiteralThisWidenedOnUse.ts, 9, 14))
+>foo.bar : Symbol(Foo.bar, Decl(objectLiteralThisWidenedOnUse.ts, 0, 15))
+>foo : Symbol(foo, Decl(objectLiteralThisWidenedOnUse.ts, 9, 14))
+>bar : Symbol(Foo.bar, Decl(objectLiteralThisWidenedOnUse.ts, 0, 15))
+  }
+};

tests/baselines/reference/objectLiteralThisWidenedOnUse.types

@@ -0,0 +1,47 @@
+=== tests/cases/compiler/objectLiteralThisWidenedOnUse.ts ===
+interface Foo { bar: boolean; }
+>bar : boolean
+
+var GlobalIns = {
+>GlobalIns : { prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }
+>{  prop1: 1,  prop2: 2,  prop3: 3,  test () {    this.accept_foo(this);  },  accept_foo (foo: Foo): boolean {    return !!foo && !!foo.bar;  }} : { prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }
+
+  prop1: 1,
+>prop1 : number
+>1 : 1
+
+  prop2: 2,
+>prop2 : number
+>2 : 2
+
+  prop3: 3,
+>prop3 : number
+>3 : 3
+
+  test () {
+>test : () => void
+
+    this.accept_foo(this);
+>this.accept_foo(this) : boolean
+>this.accept_foo : (foo: Foo) => boolean
+>this : { prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }
+>accept_foo : (foo: Foo) => boolean
+>this : { prop1: number; prop2: number; prop3: number; test(): void; accept_foo(foo: Foo): boolean; }
+
+  },
+  accept_foo (foo: Foo): boolean {
+>accept_foo : (foo: Foo) => boolean
+>foo : Foo
+
+    return !!foo && !!foo.bar;
+>!!foo && !!foo.bar : boolean
+>!!foo : boolean
+>!foo : boolean
+>foo : Foo
+>!!foo.bar : boolean
+>!foo.bar : boolean
+>foo.bar : boolean
+>foo : Foo
+>bar : boolean
+  }
+};

tests/cases/compiler/objectLiteralThisWidenedOnUse.ts

@@ -0,0 +1,14 @@
+// @noImplicitThis: true
+interface Foo { bar: boolean; }
+
+var GlobalIns = {
+  prop1: 1,
+  prop2: 2,
+  prop3: 3,
+  test () {
+    this.accept_foo(this);
+  },
+  accept_foo (foo: Foo): boolean {
+    return !!foo && !!foo.bar;
+  }
+};