Handle generic mapped types in getTypeOfPropertyOfContextualType. (#27586)

* Handle generic mapped types in getTypeOfPropertyOfContextualType. The changes to existing baselines look acceptable to me. Fixes #24694. * Minor reorganization, add test case from @yortus
2026-05-09 07:55:10 -05:00 · 2019-03-12 17:13:32 -04:00
parent d2476759e2
commit 6c6f216d0d
10 changed files with 392 additions and 7 deletions
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -10017,13 +10017,17 @@ namespace ts {
            // that substitutes the index type for P. For example, for an index access { [P in K]: Box<T[P]> }[X], we
            // construct the type Box<T[X]>.
            if (isGenericMappedType(objectType)) {
-                const mapper = createTypeMapper([getTypeParameterFromMappedType(objectType)], [type.indexType]);
-                const templateMapper = combineTypeMappers(objectType.mapper, mapper);
-                return type.simplified = mapType(instantiateType(getTemplateTypeFromMappedType(objectType), templateMapper), getSimplifiedType);
+                return type.simplified = mapType(substituteIndexedMappedType(objectType, type.indexType), getSimplifiedType);
            }
            return type.simplified = type;
        }

+        function substituteIndexedMappedType(objectType: MappedType, index: Type) {
+            const mapper = createTypeMapper([getTypeParameterFromMappedType(objectType)], [index]);
+            const templateMapper = combineTypeMappers(objectType.mapper, mapper);
+            return instantiateType(getTemplateTypeFromMappedType(objectType), templateMapper);
+        }
+
        function getIndexedAccessType(objectType: Type, indexType: Type, accessNode?: ElementAccessExpression | IndexedAccessTypeNode | PropertyName | BindingName | SyntheticExpression, missingType = accessNode ? errorType : unknownType): Type {
            if (objectType === wildcardType || indexType === wildcardType) {
                return wildcardType;
@@ -17831,7 +17835,15 @@ namespace ts {

        function getTypeOfPropertyOfContextualType(type: Type, name: __String) {
            return mapType(type, t => {
-                if (t.flags & TypeFlags.StructuredType) {
+                if (isGenericMappedType(t)) {
+                    const constraint = getConstraintTypeFromMappedType(t);
+                    const constraintOfConstraint = getBaseConstraintOfType(constraint) || constraint;
+                    const propertyNameType = getLiteralType(unescapeLeadingUnderscores(name));
+                    if (isTypeAssignableTo(propertyNameType, constraintOfConstraint)) {
+                        return substituteIndexedMappedType(t, propertyNameType);
+                    }
+                }
+                else if (t.flags & TypeFlags.StructuredType) {
                    const prop = getPropertyOfType(t, name);
                    if (prop) {
                        return getTypeOfSymbol(prop);
--- a/tests/baselines/reference/contextualPropertyOfGenericMappedType.js
+++ b/tests/baselines/reference/contextualPropertyOfGenericMappedType.js
@@ -0,0 +1,10 @@
+//// [contextualPropertyOfGenericMappedType.ts]
+// Repro for #24694
+
+declare function f<T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }): void;
+f({ data: 0 }, { data(value, key) {} });
+
+
+//// [contextualPropertyOfGenericMappedType.js]
+// Repro for #24694
+f({ data: 0 }, { data: function (value, key) { } });
--- a/tests/baselines/reference/contextualPropertyOfGenericMappedType.symbols
+++ b/tests/baselines/reference/contextualPropertyOfGenericMappedType.symbols
@@ -0,0 +1,24 @@
+=== tests/cases/compiler/contextualPropertyOfGenericMappedType.ts ===
+// Repro for #24694
+
+declare function f<T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }): void;
+>f : Symbol(f, Decl(contextualPropertyOfGenericMappedType.ts, 0, 0))
+>T : Symbol(T, Decl(contextualPropertyOfGenericMappedType.ts, 2, 19))
+>data : Symbol(data, Decl(contextualPropertyOfGenericMappedType.ts, 2, 37))
+>T : Symbol(T, Decl(contextualPropertyOfGenericMappedType.ts, 2, 19))
+>handlers : Symbol(handlers, Decl(contextualPropertyOfGenericMappedType.ts, 2, 45))
+>P : Symbol(P, Decl(contextualPropertyOfGenericMappedType.ts, 2, 59))
+>T : Symbol(T, Decl(contextualPropertyOfGenericMappedType.ts, 2, 19))
+>value : Symbol(value, Decl(contextualPropertyOfGenericMappedType.ts, 2, 75))
+>T : Symbol(T, Decl(contextualPropertyOfGenericMappedType.ts, 2, 19))
+>P : Symbol(P, Decl(contextualPropertyOfGenericMappedType.ts, 2, 59))
+>prop : Symbol(prop, Decl(contextualPropertyOfGenericMappedType.ts, 2, 87))
+>P : Symbol(P, Decl(contextualPropertyOfGenericMappedType.ts, 2, 59))
+
+f({ data: 0 }, { data(value, key) {} });
+>f : Symbol(f, Decl(contextualPropertyOfGenericMappedType.ts, 0, 0))
+>data : Symbol(data, Decl(contextualPropertyOfGenericMappedType.ts, 3, 3))
+>data : Symbol(data, Decl(contextualPropertyOfGenericMappedType.ts, 3, 16))
+>value : Symbol(value, Decl(contextualPropertyOfGenericMappedType.ts, 3, 22))
+>key : Symbol(key, Decl(contextualPropertyOfGenericMappedType.ts, 3, 28))
+
--- a/tests/baselines/reference/contextualPropertyOfGenericMappedType.types
+++ b/tests/baselines/reference/contextualPropertyOfGenericMappedType.types
@@ -0,0 +1,21 @@
+=== tests/cases/compiler/contextualPropertyOfGenericMappedType.ts ===
+// Repro for #24694
+
+declare function f<T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }): void;
+>f : <T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }) => void
+>data : T
+>handlers : { [P in keyof T]: (value: T[P], prop: P) => void; }
+>value : T[P]
+>prop : P
+
+f({ data: 0 }, { data(value, key) {} });
+>f({ data: 0 }, { data(value, key) {} }) : void
+>f : <T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }) => void
+>{ data: 0 } : { data: number; }
+>data : number
+>0 : 0
+>{ data(value, key) {} } : { data(value: number, key: "data"): void; }
+>data : (value: number, key: "data") => void
+>value : number
+>key : "data"
+
--- a/tests/baselines/reference/mappedTypeContextualTypesApplied.js
+++ b/tests/baselines/reference/mappedTypeContextualTypesApplied.js
@@ -0,0 +1,36 @@
+//// [mappedTypeContextualTypesApplied.ts]
+type TakeString = (s: string) => any;
+
+// Various functions accepting an object whose properties are TakeString functions.
+// Note these all use mapped types.
+declare function mapped1<T extends {[P in string]: TakeString}>(obj: T): void;
+declare function mapped2<T extends {[P in keyof T]: TakeString}>(obj: T): void;
+declare function mapped3<T extends {[P in keyof any]: TakeString}>(obj: T): void;
+declare function mapped4<T>(obj: T & {[P in keyof T]: TakeString}): void;
+declare function mapped5<T, K extends keyof T>(obj: T & {[P in K]: TakeString}): void;
+declare function mapped6<K extends string>(obj: {[P in K]: TakeString}): void;
+declare function mapped7<K extends keyof any>(obj: {[P in K]: TakeString}): void;
+declare function mapped8<K extends 'foo'>(obj: {[P in K]: TakeString}): void;
+declare function mapped9<K extends 'foo'|'bar'>(obj: {[P in K]: TakeString}): void;
+
+mapped1({foo: s => 42});
+mapped2({foo: s => 42});
+mapped3({foo: s => 42});
+mapped4({foo: s => 42});
+mapped5({foo: s => 42});
+mapped6({foo: s => 42});
+mapped7({foo: s => 42});
+mapped8({foo: s => 42});
+mapped9({foo: s => 42});
+
+//// [mappedTypeContextualTypesApplied.js]
+"use strict";
+mapped1({ foo: function (s) { return 42; } });
+mapped2({ foo: function (s) { return 42; } });
+mapped3({ foo: function (s) { return 42; } });
+mapped4({ foo: function (s) { return 42; } });
+mapped5({ foo: function (s) { return 42; } });
+mapped6({ foo: function (s) { return 42; } });
+mapped7({ foo: function (s) { return 42; } });
+mapped8({ foo: function (s) { return 42; } });
+mapped9({ foo: function (s) { return 42; } });
--- a/tests/baselines/reference/mappedTypeContextualTypesApplied.symbols
+++ b/tests/baselines/reference/mappedTypeContextualTypesApplied.symbols
@@ -0,0 +1,129 @@
+=== tests/cases/compiler/mappedTypeContextualTypesApplied.ts ===
+type TakeString = (s: string) => any;
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 0, 19))
+
+// Various functions accepting an object whose properties are TakeString functions.
+// Note these all use mapped types.
+declare function mapped1<T extends {[P in string]: TakeString}>(obj: T): void;
+>mapped1 : Symbol(mapped1, Decl(mappedTypeContextualTypesApplied.ts, 0, 37))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 4, 25))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 4, 37))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 4, 64))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 4, 25))
+
+declare function mapped2<T extends {[P in keyof T]: TakeString}>(obj: T): void;
+>mapped2 : Symbol(mapped2, Decl(mappedTypeContextualTypesApplied.ts, 4, 78))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 5, 25))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 5, 37))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 5, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 5, 65))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 5, 25))
+
+declare function mapped3<T extends {[P in keyof any]: TakeString}>(obj: T): void;
+>mapped3 : Symbol(mapped3, Decl(mappedTypeContextualTypesApplied.ts, 5, 79))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 6, 25))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 6, 37))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 6, 67))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 6, 25))
+
+declare function mapped4<T>(obj: T & {[P in keyof T]: TakeString}): void;
+>mapped4 : Symbol(mapped4, Decl(mappedTypeContextualTypesApplied.ts, 6, 81))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 7, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 7, 28))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 7, 25))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 7, 39))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 7, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+declare function mapped5<T, K extends keyof T>(obj: T & {[P in K]: TakeString}): void;
+>mapped5 : Symbol(mapped5, Decl(mappedTypeContextualTypesApplied.ts, 7, 73))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 8, 25))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 8, 27))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 8, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 8, 47))
+>T : Symbol(T, Decl(mappedTypeContextualTypesApplied.ts, 8, 25))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 8, 58))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 8, 27))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+declare function mapped6<K extends string>(obj: {[P in K]: TakeString}): void;
+>mapped6 : Symbol(mapped6, Decl(mappedTypeContextualTypesApplied.ts, 8, 86))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 9, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 9, 43))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 9, 50))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 9, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+declare function mapped7<K extends keyof any>(obj: {[P in K]: TakeString}): void;
+>mapped7 : Symbol(mapped7, Decl(mappedTypeContextualTypesApplied.ts, 9, 78))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 10, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 10, 46))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 10, 53))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 10, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+declare function mapped8<K extends 'foo'>(obj: {[P in K]: TakeString}): void;
+>mapped8 : Symbol(mapped8, Decl(mappedTypeContextualTypesApplied.ts, 10, 81))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 11, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 11, 42))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 11, 49))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 11, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+declare function mapped9<K extends 'foo'|'bar'>(obj: {[P in K]: TakeString}): void;
+>mapped9 : Symbol(mapped9, Decl(mappedTypeContextualTypesApplied.ts, 11, 77))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 12, 25))
+>obj : Symbol(obj, Decl(mappedTypeContextualTypesApplied.ts, 12, 48))
+>P : Symbol(P, Decl(mappedTypeContextualTypesApplied.ts, 12, 55))
+>K : Symbol(K, Decl(mappedTypeContextualTypesApplied.ts, 12, 25))
+>TakeString : Symbol(TakeString, Decl(mappedTypeContextualTypesApplied.ts, 0, 0))
+
+mapped1({foo: s => 42});
+>mapped1 : Symbol(mapped1, Decl(mappedTypeContextualTypesApplied.ts, 0, 37))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 14, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 14, 13))
+
+mapped2({foo: s => 42});
+>mapped2 : Symbol(mapped2, Decl(mappedTypeContextualTypesApplied.ts, 4, 78))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 15, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 15, 13))
+
+mapped3({foo: s => 42});
+>mapped3 : Symbol(mapped3, Decl(mappedTypeContextualTypesApplied.ts, 5, 79))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 16, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 16, 13))
+
+mapped4({foo: s => 42});
+>mapped4 : Symbol(mapped4, Decl(mappedTypeContextualTypesApplied.ts, 6, 81))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 17, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 17, 13))
+
+mapped5({foo: s => 42});
+>mapped5 : Symbol(mapped5, Decl(mappedTypeContextualTypesApplied.ts, 7, 73))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 18, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 18, 13))
+
+mapped6({foo: s => 42});
+>mapped6 : Symbol(mapped6, Decl(mappedTypeContextualTypesApplied.ts, 8, 86))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 19, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 19, 13))
+
+mapped7({foo: s => 42});
+>mapped7 : Symbol(mapped7, Decl(mappedTypeContextualTypesApplied.ts, 9, 78))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 20, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 20, 13))
+
+mapped8({foo: s => 42});
+>mapped8 : Symbol(mapped8, Decl(mappedTypeContextualTypesApplied.ts, 10, 81))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 21, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 21, 13))
+
+mapped9({foo: s => 42});
+>mapped9 : Symbol(mapped9, Decl(mappedTypeContextualTypesApplied.ts, 11, 77))
+>foo : Symbol(foo, Decl(mappedTypeContextualTypesApplied.ts, 22, 9))
+>s : Symbol(s, Decl(mappedTypeContextualTypesApplied.ts, 22, 13))
+
--- a/tests/baselines/reference/mappedTypeContextualTypesApplied.types
+++ b/tests/baselines/reference/mappedTypeContextualTypesApplied.types
@@ -0,0 +1,124 @@
+=== tests/cases/compiler/mappedTypeContextualTypesApplied.ts ===
+type TakeString = (s: string) => any;
+>TakeString : TakeString
+>s : string
+
+// Various functions accepting an object whose properties are TakeString functions.
+// Note these all use mapped types.
+declare function mapped1<T extends {[P in string]: TakeString}>(obj: T): void;
+>mapped1 : <T extends { [x: string]: TakeString; }>(obj: T) => void
+>obj : T
+
+declare function mapped2<T extends {[P in keyof T]: TakeString}>(obj: T): void;
+>mapped2 : <T extends { [P in keyof T]: TakeString; }>(obj: T) => void
+>obj : T
+
+declare function mapped3<T extends {[P in keyof any]: TakeString}>(obj: T): void;
+>mapped3 : <T extends { [x: string]: TakeString; }>(obj: T) => void
+>obj : T
+
+declare function mapped4<T>(obj: T & {[P in keyof T]: TakeString}): void;
+>mapped4 : <T>(obj: T & { [P in keyof T]: TakeString; }) => void
+>obj : T & { [P in keyof T]: TakeString; }
+
+declare function mapped5<T, K extends keyof T>(obj: T & {[P in K]: TakeString}): void;
+>mapped5 : <T, K extends keyof T>(obj: T & { [P in K]: TakeString; }) => void
+>obj : T & { [P in K]: TakeString; }
+
+declare function mapped6<K extends string>(obj: {[P in K]: TakeString}): void;
+>mapped6 : <K extends string>(obj: { [P in K]: TakeString; }) => void
+>obj : { [P in K]: TakeString; }
+
+declare function mapped7<K extends keyof any>(obj: {[P in K]: TakeString}): void;
+>mapped7 : <K extends string | number | symbol>(obj: { [P in K]: TakeString; }) => void
+>obj : { [P in K]: TakeString; }
+
+declare function mapped8<K extends 'foo'>(obj: {[P in K]: TakeString}): void;
+>mapped8 : <K extends "foo">(obj: { [P in K]: TakeString; }) => void
+>obj : { [P in K]: TakeString; }
+
+declare function mapped9<K extends 'foo'|'bar'>(obj: {[P in K]: TakeString}): void;
+>mapped9 : <K extends "foo" | "bar">(obj: { [P in K]: TakeString; }) => void
+>obj : { [P in K]: TakeString; }
+
+mapped1({foo: s => 42});
+>mapped1({foo: s => 42}) : void
+>mapped1 : <T extends { [x: string]: TakeString; }>(obj: T) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped2({foo: s => 42});
+>mapped2({foo: s => 42}) : void
+>mapped2 : <T extends { [P in keyof T]: TakeString; }>(obj: T) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped3({foo: s => 42});
+>mapped3({foo: s => 42}) : void
+>mapped3 : <T extends { [x: string]: TakeString; }>(obj: T) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped4({foo: s => 42});
+>mapped4({foo: s => 42}) : void
+>mapped4 : <T>(obj: T & { [P in keyof T]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped5({foo: s => 42});
+>mapped5({foo: s => 42}) : void
+>mapped5 : <T, K extends keyof T>(obj: T & { [P in K]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped6({foo: s => 42});
+>mapped6({foo: s => 42}) : void
+>mapped6 : <K extends string>(obj: { [P in K]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped7({foo: s => 42});
+>mapped7({foo: s => 42}) : void
+>mapped7 : <K extends string | number | symbol>(obj: { [P in K]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped8({foo: s => 42});
+>mapped8({foo: s => 42}) : void
+>mapped8 : <K extends "foo">(obj: { [P in K]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
+mapped9({foo: s => 42});
+>mapped9({foo: s => 42}) : void
+>mapped9 : <K extends "foo" | "bar">(obj: { [P in K]: TakeString; }) => void
+>{foo: s => 42} : { foo: (s: string) => number; }
+>foo : (s: string) => number
+>s => 42 : (s: string) => number
+>s : string
+>42 : 42
+
--- a/tests/baselines/reference/reverseMappedContravariantInference.types
+++ b/tests/baselines/reference/reverseMappedContravariantInference.types
@@ -11,9 +11,9 @@ conforms({ foo: (v: string) => false })({ foo: "hello" });
 >conforms({ foo: (v: string) => false })({ foo: "hello" }) : boolean
 >conforms({ foo: (v: string) => false }) : (value: { foo: string; }) => boolean
 >conforms : <T>(source: { [K in keyof T]: (val: T[K]) => boolean; }) => (value: T) => boolean
->{ foo: (v: string) => false } : { foo: (v: string) => boolean; }
->foo : (v: string) => boolean
->(v: string) => false : (v: string) => boolean
+>{ foo: (v: string) => false } : { foo: (v: string) => false; }
+>foo : (v: string) => false
+>(v: string) => false : (v: string) => false
 >v : string
 >false : false
 >{ foo: "hello" } : { foo: string; }
--- a/tests/cases/compiler/contextualPropertyOfGenericMappedType.ts
+++ b/tests/cases/compiler/contextualPropertyOfGenericMappedType.ts
@@ -0,0 +1,5 @@
+// Repro for #24694
+// @noImplicitAny: true
+
+declare function f<T extends object>(data: T, handlers: { [P in keyof T]: (value: T[P], prop: P) => void; }): void;
+f({ data: 0 }, { data(value, key) {} });
--- a/tests/cases/compiler/mappedTypeContextualTypesApplied.ts
+++ b/tests/cases/compiler/mappedTypeContextualTypesApplied.ts
@@ -0,0 +1,24 @@
+// @strict: true
+type TakeString = (s: string) => any;
+
+// Various functions accepting an object whose properties are TakeString functions.
+// Note these all use mapped types.
+declare function mapped1<T extends {[P in string]: TakeString}>(obj: T): void;
+declare function mapped2<T extends {[P in keyof T]: TakeString}>(obj: T): void;
+declare function mapped3<T extends {[P in keyof any]: TakeString}>(obj: T): void;
+declare function mapped4<T>(obj: T & {[P in keyof T]: TakeString}): void;
+declare function mapped5<T, K extends keyof T>(obj: T & {[P in K]: TakeString}): void;
+declare function mapped6<K extends string>(obj: {[P in K]: TakeString}): void;
+declare function mapped7<K extends keyof any>(obj: {[P in K]: TakeString}): void;
+declare function mapped8<K extends 'foo'>(obj: {[P in K]: TakeString}): void;
+declare function mapped9<K extends 'foo'|'bar'>(obj: {[P in K]: TakeString}): void;
+
+mapped1({foo: s => 42});
+mapped2({foo: s => 42});
+mapped3({foo: s => 42});
+mapped4({foo: s => 42});
+mapped5({foo: s => 42});
+mapped6({foo: s => 42});
+mapped7({foo: s => 42});
+mapped8({foo: s => 42});
+mapped9({foo: s => 42});