fix: reference to class expression in private method (#13429)

Co-authored-by: Henry Zhu <hi@henryzoo.com>
Co-authored-by: Federico Ciardi <fed.ciardi@gmail.com>
Co-authored-by: Nicolò Ribaudo <nicolo.ribaudo@gmail.com>

packages/babel-helper-create-class-features-plugin/src/fields.ts

@@ -669,6 +669,17 @@ const thisContextVisitor = traverse.visitors.merge([
   environmentVisitor,
 ]);
 
+const innerReferencesVisitor = {
+  ReferencedIdentifier(path, state) {
+    if (
+      path.scope.bindingIdentifierEquals(path.node.name, state.innerBinding)
+    ) {
+      state.needsClassRef = true;
+      path.node.name = state.classRef.name;
+    }
+  },
+};
+
 function replaceThisContext(
   path,
   ref,
@@ -676,8 +687,13 @@ function replaceThisContext(
   file,
   isStaticBlock,
   constantSuper,
+  innerBindingRef,
 ) {
-  const state = { classRef: ref, needsClassRef: false };
+  const state = {
+    classRef: ref,
+    needsClassRef: false,
+    innerBinding: innerBindingRef,
+  };
 
   const replacer = new ReplaceSupers({
     methodPath: path,
@@ -696,6 +712,11 @@ function replaceThisContext(
   if (isStaticBlock || path.isProperty()) {
     path.traverse(thisContextVisitor, state);
   }
+
+  if (state.classRef?.name && state.classRef.name !== innerBindingRef?.name) {
+    path.traverse(innerReferencesVisitor, state);
+  }
+
   return state.needsClassRef;
 }
 
@@ -708,6 +729,7 @@ export function buildFieldsInitNodes(
   setPublicClassFields,
   privateFieldsAsProperties,
   constantSuper,
+  innerBindingRef,
 ) {
   let needsClassRef = false;
   let injectSuperRef;
@@ -743,6 +765,7 @@ export function buildFieldsInitNodes(
         state,
         isStaticBlock,
         constantSuper,
+        innerBindingRef,
       );
       needsClassRef = needsClassRef || replaced;
     }

packages/babel-helper-create-class-features-plugin/src/index.ts

@@ -168,9 +168,9 @@ export function createClassFeaturePlugin({
 
         if (!props.length && !isDecorated) return;
 
+        const innerBinding = path.node.id;
         let ref;
-
-        if (path.isClassExpression() || !path.node.id) {
+        if (!innerBinding || path.isClassExpression()) {
           nameFunction(path);
           ref = path.scope.generateUidIdentifier("class");
         } else {
@@ -220,6 +220,7 @@ export function createClassFeaturePlugin({
               setPublicClassFields ?? loose,
               privateFieldsAsProperties ?? loose,
               constantSuper ?? loose,
+              innerBinding,
             ));
         }
 

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-field/exec.js

@@ -0,0 +1,15 @@
+const f = class Foo {
+  static #x = Foo;
+  static y = Foo;
+
+  static extract() {
+    return {
+      x: Foo.#x,
+      y: Foo.y,
+    }
+  }
+};
+
+const { x, y } = f.extract();
+expect(x).toBe(f)
+expect(y).toBe(f)

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-field/input.js

@@ -0,0 +1,4 @@
+const f = class Foo {
+  static #x = Foo;
+  static y = Foo;
+}

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-field/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["proposal-class-properties", "transform-block-scoping"]
+}

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-field/output.js

@@ -0,0 +1,6 @@
+var _class, _temp, _x;
+
+var f = (_temp = _class = class Foo {}, _x = {
+  writable: true,
+  value: _class
+}, babelHelpers.defineProperty(_class, "y", _class), _temp);

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-method/exec.js

@@ -0,0 +1,31 @@
+const f = class Foo {
+  static #bar() {
+    return Foo;
+  }
+
+  static #method() {
+    return function inner() {
+      return Foo;
+    };
+  }
+  static #method_shadowed() {
+    new Foo();
+    return function inner() {
+      let Foo = 3;
+      return Foo;
+    }
+  }
+
+  static extract() {
+    return {
+      bar: Foo.#bar,
+      method: Foo.#method,
+      method_shadowed: Foo.#method_shadowed
+    }
+  }
+};
+
+const { bar, method, method_shadowed } = f.extract();
+expect(bar()).toBe(f)
+expect(method()()).toBe(f)
+expect(method_shadowed()()).toBe(3)

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-method/input.js

@@ -0,0 +1,18 @@
+const f = class Foo {
+  static #bar() {
+    return Foo;
+  }
+
+  static #method() {
+    return function inner() {
+      return Foo;
+    };
+  }
+  static #method_shadowed() {
+    new Foo();
+    return function inner() {
+      let Foo = 3;
+      return Foo;
+    }
+  }
+}

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-method/options.json

@@ -0,0 +1,3 @@
+{
+  "plugins": ["proposal-class-properties", "transform-block-scoping"]
+}

packages/babel-plugin-proposal-class-properties/test/fixtures/private/static-self-method/output.js

@@ -0,0 +1,21 @@
+var _class;
+
+var f = _class = class Foo {};
+
+function _bar() {
+  return _class;
+}
+
+function _method() {
+  return function inner() {
+    return _class;
+  };
+}
+
+function _method_shadowed() {
+  new _class();
+  return function inner() {
+    var Foo = 3;
+    return Foo;
+  };
+}