Port TypeScript #62722: Widen reverse mapped type properties

internal/checker/inference.go

@@ -1024,7 +1024,7 @@ func (c *Checker) inferReverseMappedTypeWorker(source *Type, target *Type, const
 	templateType := c.getTemplateTypeFromMappedType(target)
 	inference := newInferenceInfo(typeParameter)
 	c.inferTypes([]*InferenceInfo{inference}, source, templateType, InferencePriorityNone, false)
-	return core.OrElse(c.getTypeFromInference(inference), c.unknownType)
+	return c.getWidenedType(core.OrElse(c.getTypeFromInference(inference), c.unknownType))
 }
 
 func (c *Checker) resolveReverseMappedTypeMembers(t *Type) {

testdata/baselines/reference/submodule/compiler/reverseMappedTypeInferenceWidening1.types

@@ -115,9 +115,9 @@ result2.booleanFlag; // boolean
 >booleanFlag : boolean
 
 result2.booleanFlagDefault; // boolean
->result2.booleanFlagDefault : never
+>result2.booleanFlagDefault : boolean
 >result2 : TypeFlag<{ booleanFlag: { type: BooleanConstructor; }; booleanFlagDefault: { type: BooleanConstructor; default: boolean; }; }>
->booleanFlagDefault : never
+>booleanFlagDefault : boolean
 
 declare function fn3<Options extends Flags>(
 >fn3 : <Options extends Flags>(options: Readonly<Options>) => Options

testdata/baselines/reference/submodule/compiler/reverseMappedTypeInferenceWidening2.types

@@ -10,10 +10,10 @@ declare function test1<T extends Record<string, { prop: unknown }>>(arg: {
 }): T;
 
 const res1 = test1({
->res1 : Record<string, { prop: unknown; }>
->test1({  foo: {    prop: 1,    prop2: "",  },  bar: {    prop: true,    prop2: null,  },}) : Record<string, { prop: unknown; }>
+>res1 : { foo: { prop: number; prop2: string; }; bar: { prop: boolean; prop2: null; }; }
+>test1({  foo: {    prop: 1,    prop2: "",  },  bar: {    prop: true,    prop2: null,  },}) : { foo: { prop: number; prop2: string; }; bar: { prop: boolean; prop2: null; }; }
 >test1 : <T extends Record<string, { prop: unknown; }>>(arg: { [K in keyof T]: T[K]; }) => T
->{  foo: {    prop: 1,    prop2: "",  },  bar: {    prop: true,    prop2: null,  },} : { foo: { prop: number; prop2: string; }; bar: { prop: boolean; prop2: null; }; }
+>{  foo: {    prop: 1,    prop2: "",  },  bar: {    prop: true,    prop2: null,  },} : { foo: { prop: number; prop2: string; }; bar: { prop: true; prop2: null; }; }
 
   foo: {
 >foo : { prop: number; prop2: string; }
@@ -29,11 +29,11 @@ const res1 = test1({
 
   },
   bar: {
->bar : { prop: boolean; prop2: null; }
->{    prop: true,    prop2: null,  } : { prop: boolean; prop2: null; }
+>bar : { prop: true; prop2: null; }
+>{    prop: true,    prop2: null,  } : { prop: true; prop2: null; }
 
     prop: true,
->prop : boolean
+>prop : true
 >true : true
 
     prop2: null,