Additional fix to issue #50509

src/compiler/checker.ts

@@ -28672,6 +28672,22 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
         });
     }
 
+    function getThisTypeOfObjectLiteralFromContextualType(containingLiteral: ObjectLiteralExpression, contextualType: Type | undefined) {
+        let literal = containingLiteral;
+        let type = contextualType;
+        while (type) {
+            const thisType = getThisTypeFromContextualType(type);
+            if (thisType) {
+                return thisType;
+            }
+            if (literal.parent.kind !== SyntaxKind.PropertyAssignment) {
+                break;
+            }
+            literal = literal.parent.parent as ObjectLiteralExpression;
+            type = getApparentTypeOfContextualType(literal, /*contextFlags*/ undefined);
+        }
+    }
+
     function getContextualThisParameterType(func: SignatureDeclaration): Type | undefined {
         if (func.kind === SyntaxKind.ArrowFunction) {
             return undefined;
@@ -28693,18 +28709,9 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 // that includes a ThisType<T>. If so, T is the contextual type for 'this'. We continue looking in
                 // any directly enclosing object literals.
                 const contextualType = getApparentTypeOfContextualType(containingLiteral, /*contextFlags*/ undefined);
-                let literal = containingLiteral;
-                let type = contextualType;
-                while (type) {
-                    const thisType = getThisTypeFromContextualType(type);
-                    if (thisType) {
-                        return instantiateType(thisType, getMapperFromContext(getInferenceContext(containingLiteral)));
-                    }
-                    if (literal.parent.kind !== SyntaxKind.PropertyAssignment) {
-                        break;
-                    }
-                    literal = literal.parent.parent as ObjectLiteralExpression;
-                    type = getApparentTypeOfContextualType(literal, /*contextFlags*/ undefined);
+                const thisType = getThisTypeOfObjectLiteralFromContextualType(containingLiteral, contextualType);
+                if (thisType) {
+                    return instantiateType(thisType, getMapperFromContext(getInferenceContext(containingLiteral)));
                 }
                 // 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
@@ -45424,7 +45431,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                 const containingLiteral = getContainingObjectLiteral(container);
                 if (containingLiteral) {
                     const contextualType = getApparentTypeOfContextualType(containingLiteral, /*contextFlags*/ undefined);
-                    const type = contextualType && getThisTypeFromContextualType(contextualType);
+                    const type = getThisTypeOfObjectLiteralFromContextualType(containingLiteral, contextualType);
                     return type && !isTypeAny(type);
                 }
             }

tests/baselines/reference/findAllRefsJsThisPropertyAssignment2.baseline.jsonc

@@ -0,0 +1,149 @@
+// === findAllReferences ===
+// === /tests/cases/fourslash/infer.d.ts ===
+// export declare function infer(o: { m: Record<string, Function> } & ThisType<{ <|[|{| isWriteAccess: true |}x|]: number|> }>): void;
+
+// === /tests/cases/fourslash/a.js ===
+// import { infer } from "./infer";
+// infer({
+//     m: {
+//         initData() {
+//             <|this.[|{| isWriteAccess: true |}x|] = 1;|>
+//             this./*FIND ALL REFS*/[|x|];
+//         },
+//     }
+// });
+
+// === /tests/cases/fourslash/b.ts ===
+// import { infer } from "./infer";
+// infer({
+//     m: {
+//         initData() {
+//             this.[|{| isWriteAccess: true |}x|] = 1;
+//             this.[|x|];
+//         },
+//     }
+// });
+
+  // === Definitions ===
+  // === /tests/cases/fourslash/infer.d.ts ===
+  // export declare function infer(o: { m: Record<string, Function> } & ThisType<{ <|[|x|]: number|> }>): void;
+
+  // === Details ===
+  [
+   {
+    "containerKind": "",
+    "containerName": "",
+    "kind": "property",
+    "name": "(property) x: number",
+    "displayParts": [
+     {
+      "text": "(",
+      "kind": "punctuation"
+     },
+     {
+      "text": "property",
+      "kind": "text"
+     },
+     {
+      "text": ")",
+      "kind": "punctuation"
+     },
+     {
+      "text": " ",
+      "kind": "space"
+     },
+     {
+      "text": "x",
+      "kind": "propertyName"
+     },
+     {
+      "text": ":",
+      "kind": "punctuation"
+     },
+     {
+      "text": " ",
+      "kind": "space"
+     },
+     {
+      "text": "number",
+      "kind": "keyword"
+     }
+    ]
+   }
+  ]
+
+
+
+// === findAllReferences ===
+// === /tests/cases/fourslash/infer.d.ts ===
+// export declare function infer(o: { m: Record<string, Function> } & ThisType<{ <|[|{| isWriteAccess: true |}x|]: number|> }>): void;
+
+// === /tests/cases/fourslash/a.js ===
+// import { infer } from "./infer";
+// infer({
+//     m: {
+//         initData() {
+//             <|this.[|{| isWriteAccess: true |}x|] = 1;|>
+//             this.[|x|];
+//         },
+//     }
+// });
+
+// === /tests/cases/fourslash/b.ts ===
+// import { infer } from "./infer";
+// infer({
+//     m: {
+//         initData() {
+//             this.[|{| isWriteAccess: true |}x|] = 1;
+//             this./*FIND ALL REFS*/[|x|];
+//         },
+//     }
+// });
+
+  // === Definitions ===
+  // === /tests/cases/fourslash/infer.d.ts ===
+  // export declare function infer(o: { m: Record<string, Function> } & ThisType<{ <|[|x|]: number|> }>): void;
+
+  // === Details ===
+  [
+   {
+    "containerKind": "",
+    "containerName": "",
+    "kind": "property",
+    "name": "(property) x: number",
+    "displayParts": [
+     {
+      "text": "(",
+      "kind": "punctuation"
+     },
+     {
+      "text": "property",
+      "kind": "text"
+     },
+     {
+      "text": ")",
+      "kind": "punctuation"
+     },
+     {
+      "text": " ",
+      "kind": "space"
+     },
+     {
+      "text": "x",
+      "kind": "propertyName"
+     },
+     {
+      "text": ":",
+      "kind": "punctuation"
+     },
+     {
+      "text": " ",
+      "kind": "space"
+     },
+     {
+      "text": "number",
+      "kind": "keyword"
+     }
+    ]
+   }
+  ]

tests/cases/fourslash/findAllRefsJsThisPropertyAssignment2.ts

@@ -0,0 +1,31 @@
+/// <reference path="fourslash.ts" />
+
+// @allowJs: true
+// @noImplicitThis: true
+
+// @Filename: infer.d.ts
+//// export declare function infer(o: { m: Record<string, Function> } & ThisType<{ x: number }>): void;
+
+// @Filename: a.js
+//// import { infer } from "./infer";
+//// infer({
+////     m: {
+////         initData() {
+////             this.x = 1;
+////             this./*1*/x;
+////         },
+////     }
+//// });
+
+// @Filename: b.ts
+//// import { infer } from "./infer";
+//// infer({
+////     m: {
+////         initData() {
+////             this.x = 1;
+////             this./*2*/x;
+////         },
+////     }
+//// });
+
+verify.baselineFindAllReferences("1", "2");