Fixed symbol lookup for binding expando properties in blocks (#56552)

src/compiler/binder.ts

@@ -3309,7 +3309,7 @@ function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
 
     function bindSpecialPropertyAssignment(node: BindablePropertyAssignmentExpression) {
         // Class declarations in Typescript do not allow property declarations
-        const parentSymbol = lookupSymbolForPropertyAccess(node.left.expression, container) || lookupSymbolForPropertyAccess(node.left.expression, blockScopeContainer);
+        const parentSymbol = lookupSymbolForPropertyAccess(node.left.expression, blockScopeContainer) || lookupSymbolForPropertyAccess(node.left.expression, container);
         if (!isInJSFile(node) && !isFunctionSymbol(parentSymbol)) {
             return;
         }
@@ -3428,7 +3428,7 @@ function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
     }
 
     function bindPropertyAssignment(name: BindableStaticNameExpression, propertyAccess: BindableStaticAccessExpression, isPrototypeProperty: boolean, containerIsClass: boolean) {
-        let namespaceSymbol = lookupSymbolForPropertyAccess(name, container) || lookupSymbolForPropertyAccess(name, blockScopeContainer);
+        let namespaceSymbol = lookupSymbolForPropertyAccess(name, blockScopeContainer) || lookupSymbolForPropertyAccess(name, container);
         const isToplevel = isTopLevelNamespaceAssignment(propertyAccess);
         namespaceSymbol = bindPotentiallyMissingNamespaces(namespaceSymbol, propertyAccess.expression, isToplevel, isPrototypeProperty, containerIsClass);
         bindPotentiallyNewExpandoMemberToNamespace(propertyAccess, namespaceSymbol, isPrototypeProperty);

tests/baselines/reference/expandoFunctionBlockShadowing.js

@@ -0,0 +1,51 @@
+//// [tests/cases/compiler/expandoFunctionBlockShadowing.ts] ////
+
+//// [expandoFunctionBlockShadowing.ts]
+// https://github.com/microsoft/TypeScript/issues/56538
+
+export function X() {}
+if (Math.random()) {
+  const X: { test?: any } = {};
+  X.test = 1;
+}
+
+export function Y() {}
+Y.test = "foo";
+const aliasTopY = Y;
+if (Math.random()) {
+  const Y = function Y() {}
+  Y.test = 42;
+
+  const topYcheck: { (): void; test: string } = aliasTopY;
+  const blockYcheck: { (): void; test: number } = Y;
+}
+
+//// [expandoFunctionBlockShadowing.js]
+"use strict";
+// https://github.com/microsoft/TypeScript/issues/56538
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.Y = exports.X = void 0;
+function X() { }
+exports.X = X;
+if (Math.random()) {
+    var X_1 = {};
+    X_1.test = 1;
+}
+function Y() { }
+exports.Y = Y;
+Y.test = "foo";
+var aliasTopY = Y;
+if (Math.random()) {
+    var Y_1 = function Y() { };
+    Y_1.test = 42;
+    var topYcheck = aliasTopY;
+    var blockYcheck = Y_1;
+}
+
+
+//// [expandoFunctionBlockShadowing.d.ts]
+export declare function X(): void;
+export declare function Y(): void;
+export declare namespace Y {
+    var test: string;
+}

tests/baselines/reference/expandoFunctionBlockShadowing.symbols

@@ -0,0 +1,59 @@
+//// [tests/cases/compiler/expandoFunctionBlockShadowing.ts] ////
+
+=== expandoFunctionBlockShadowing.ts ===
+// https://github.com/microsoft/TypeScript/issues/56538
+
+export function X() {}
+>X : Symbol(X, Decl(expandoFunctionBlockShadowing.ts, 0, 0))
+
+if (Math.random()) {
+>Math.random : Symbol(Math.random, Decl(lib.es5.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.es5.d.ts, --, --))
+
+  const X: { test?: any } = {};
+>X : Symbol(X, Decl(expandoFunctionBlockShadowing.ts, 4, 7))
+>test : Symbol(test, Decl(expandoFunctionBlockShadowing.ts, 4, 12))
+
+  X.test = 1;
+>X.test : Symbol(test, Decl(expandoFunctionBlockShadowing.ts, 4, 12))
+>X : Symbol(X, Decl(expandoFunctionBlockShadowing.ts, 4, 7))
+>test : Symbol(test, Decl(expandoFunctionBlockShadowing.ts, 4, 12))
+}
+
+export function Y() {}
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 6, 1), Decl(expandoFunctionBlockShadowing.ts, 8, 22))
+
+Y.test = "foo";
+>Y.test : Symbol(Y.test, Decl(expandoFunctionBlockShadowing.ts, 8, 22))
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 6, 1), Decl(expandoFunctionBlockShadowing.ts, 8, 22))
+>test : Symbol(Y.test, Decl(expandoFunctionBlockShadowing.ts, 8, 22))
+
+const aliasTopY = Y;
+>aliasTopY : Symbol(aliasTopY, Decl(expandoFunctionBlockShadowing.ts, 10, 5))
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 6, 1), Decl(expandoFunctionBlockShadowing.ts, 8, 22))
+
+if (Math.random()) {
+>Math.random : Symbol(Math.random, Decl(lib.es5.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>random : Symbol(Math.random, Decl(lib.es5.d.ts, --, --))
+
+  const Y = function Y() {}
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 12, 7))
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 12, 11))
+
+  Y.test = 42;
+>Y.test : Symbol(Y.test, Decl(expandoFunctionBlockShadowing.ts, 12, 27))
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 12, 7))
+>test : Symbol(Y.test, Decl(expandoFunctionBlockShadowing.ts, 12, 27))
+
+  const topYcheck: { (): void; test: string } = aliasTopY;
+>topYcheck : Symbol(topYcheck, Decl(expandoFunctionBlockShadowing.ts, 15, 7))
+>test : Symbol(test, Decl(expandoFunctionBlockShadowing.ts, 15, 30))
+>aliasTopY : Symbol(aliasTopY, Decl(expandoFunctionBlockShadowing.ts, 10, 5))
+
+  const blockYcheck: { (): void; test: number } = Y;
+>blockYcheck : Symbol(blockYcheck, Decl(expandoFunctionBlockShadowing.ts, 16, 7))
+>test : Symbol(test, Decl(expandoFunctionBlockShadowing.ts, 16, 32))
+>Y : Symbol(Y, Decl(expandoFunctionBlockShadowing.ts, 12, 7))
+}

tests/baselines/reference/expandoFunctionBlockShadowing.types

@@ -0,0 +1,69 @@
+//// [tests/cases/compiler/expandoFunctionBlockShadowing.ts] ////
+
+=== expandoFunctionBlockShadowing.ts ===
+// https://github.com/microsoft/TypeScript/issues/56538
+
+export function X() {}
+>X : () => void
+
+if (Math.random()) {
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+
+  const X: { test?: any } = {};
+>X : { test?: any; }
+>test : any
+>{} : {}
+
+  X.test = 1;
+>X.test = 1 : 1
+>X.test : any
+>X : { test?: any; }
+>test : any
+>1 : 1
+}
+
+export function Y() {}
+>Y : typeof Y
+
+Y.test = "foo";
+>Y.test = "foo" : "foo"
+>Y.test : string
+>Y : typeof Y
+>test : string
+>"foo" : "foo"
+
+const aliasTopY = Y;
+>aliasTopY : typeof Y
+>Y : typeof Y
+
+if (Math.random()) {
+>Math.random() : number
+>Math.random : () => number
+>Math : Math
+>random : () => number
+
+  const Y = function Y() {}
+>Y : { (): void; test: number; }
+>function Y() {} : { (): void; test: number; }
+>Y : { (): void; test: number; }
+
+  Y.test = 42;
+>Y.test = 42 : 42
+>Y.test : number
+>Y : { (): void; test: number; }
+>test : number
+>42 : 42
+
+  const topYcheck: { (): void; test: string } = aliasTopY;
+>topYcheck : { (): void; test: string; }
+>test : string
+>aliasTopY : typeof import("expandoFunctionBlockShadowing").Y
+
+  const blockYcheck: { (): void; test: number } = Y;
+>blockYcheck : { (): void; test: number; }
+>test : number
+>Y : { (): void; test: number; }
+}

tests/cases/compiler/expandoFunctionBlockShadowing.ts

@@ -0,0 +1,21 @@
+// @strict: true
+// @declaration: true
+
+// https://github.com/microsoft/TypeScript/issues/56538
+
+export function X() {}
+if (Math.random()) {
+  const X: { test?: any } = {};
+  X.test = 1;
+}
+
+export function Y() {}
+Y.test = "foo";
+const aliasTopY = Y;
+if (Math.random()) {
+  const Y = function Y() {}
+  Y.test = 42;
+
+  const topYcheck: { (): void; test: string } = aliasTopY;
+  const blockYcheck: { (): void; test: number } = Y;
+}