Merge pull request #13769 from Microsoft/fixTypeParameterScopeCheck

Fix type parameter scope check

Author: ahejlsberg

src/compiler/checker.ts

@@ -6864,6 +6864,11 @@ namespace ts {
                             }
                         }
                         break;
+                    case SyntaxKind.MappedType:
+                        if (contains(mappedTypes, getDeclaredTypeOfTypeParameter(getSymbolOfNode((<MappedTypeNode>node).typeParameter)))) {
+                            return true;
+                        }
+                        break;
                     case SyntaxKind.JSDocFunctionType:
                         const func = node as JSDocFunctionType;
                         for (const p of func.parameters) {

tests/baselines/reference/keyofAndIndexedAccess.js

@@ -516,6 +516,16 @@ class B extends A<{ x: number}> {
 		p.x;
 	}
 }
+
+// Repro from #13749
+
+class Form<T> {
+    private childFormFactories: {[K in keyof T]: (v: T[K]) => Form<T[K]>}
+
+    public set<K extends keyof T>(prop: K, value: T[K]) {
+        this.childFormFactories[prop](value)
+    }
+}
 
 
 //// [keyofAndIndexedAccess.js]
@@ -862,6 +872,15 @@ var B = (function (_super) {
     };
     return B;
 }(A));
+// Repro from #13749
+var Form = (function () {
+    function Form() {
+    }
+    Form.prototype.set = function (prop, value) {
+        this.childFormFactories[prop](value);
+    };
+    return Form;
+}());
 
 
 //// [keyofAndIndexedAccess.d.ts]
@@ -1104,3 +1123,7 @@ declare class B extends A<{
 }> {
     f(p: this["props"]): void;
 }
+declare class Form<T> {
+    private childFormFactories;
+    set<K extends keyof T>(prop: K, value: T[K]): void;
+}

tests/baselines/reference/keyofAndIndexedAccess.symbols

@@ -1844,3 +1844,39 @@ class B extends A<{ x: number}> {
 	}
 }
 
+// Repro from #13749
+
+class Form<T> {
+>Form : Symbol(Form, Decl(keyofAndIndexedAccess.ts, 516, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+
+    private childFormFactories: {[K in keyof T]: (v: T[K]) => Form<T[K]>}
+>childFormFactories : Symbol(Form.childFormFactories, Decl(keyofAndIndexedAccess.ts, 520, 15))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 521, 34))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+>v : Symbol(v, Decl(keyofAndIndexedAccess.ts, 521, 50))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 521, 34))
+>Form : Symbol(Form, Decl(keyofAndIndexedAccess.ts, 516, 1))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 521, 34))
+
+    public set<K extends keyof T>(prop: K, value: T[K]) {
+>set : Symbol(Form.set, Decl(keyofAndIndexedAccess.ts, 521, 73))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 523, 15))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 523, 34))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 523, 15))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 523, 42))
+>T : Symbol(T, Decl(keyofAndIndexedAccess.ts, 520, 11))
+>K : Symbol(K, Decl(keyofAndIndexedAccess.ts, 523, 15))
+
+        this.childFormFactories[prop](value)
+>this.childFormFactories : Symbol(Form.childFormFactories, Decl(keyofAndIndexedAccess.ts, 520, 15))
+>this : Symbol(Form, Decl(keyofAndIndexedAccess.ts, 516, 1))
+>childFormFactories : Symbol(Form.childFormFactories, Decl(keyofAndIndexedAccess.ts, 520, 15))
+>prop : Symbol(prop, Decl(keyofAndIndexedAccess.ts, 523, 34))
+>value : Symbol(value, Decl(keyofAndIndexedAccess.ts, 523, 42))
+    }
+}
+

tests/baselines/reference/keyofAndIndexedAccess.types

@@ -2166,3 +2166,41 @@ class B extends A<{ x: number}> {
 	}
 }
 
+// Repro from #13749
+
+class Form<T> {
+>Form : Form<T>
+>T : T
+
+    private childFormFactories: {[K in keyof T]: (v: T[K]) => Form<T[K]>}
+>childFormFactories : { [K in keyof T]: (v: T[K]) => Form<T[K]>; }
+>K : K
+>T : T
+>v : T[K]
+>T : T
+>K : K
+>Form : Form<T>
+>T : T
+>K : K
+
+    public set<K extends keyof T>(prop: K, value: T[K]) {
+>set : <K extends keyof T>(prop: K, value: T[K]) => void
+>K : K
+>T : T
+>prop : K
+>K : K
+>value : T[K]
+>T : T
+>K : K
+
+        this.childFormFactories[prop](value)
+>this.childFormFactories[prop](value) : Form<T[K]>
+>this.childFormFactories[prop] : (v: T[K]) => Form<T[K]>
+>this.childFormFactories : { [K in keyof T]: (v: T[K]) => Form<T[K]>; }
+>this : this
+>childFormFactories : { [K in keyof T]: (v: T[K]) => Form<T[K]>; }
+>prop : K
+>value : T[K]
+    }
+}
+

tests/cases/conformance/types/keyof/keyofAndIndexedAccess.ts

@@ -517,3 +517,13 @@ class B extends A<{ x: number}> {
 		p.x;
 	}
 }
+
+// Repro from #13749
+
+class Form<T> {
+    private childFormFactories: {[K in keyof T]: (v: T[K]) => Form<T[K]>}
+
+    public set<K extends keyof T>(prop: K, value: T[K]) {
+        this.childFormFactories[prop](value)
+    }
+}