Fix support for private fields

packages/babel-helper-member-expression-to-functions/src/index.ts

@@ -169,12 +169,12 @@ const handle = {
       const willEndPathCastToBoolean = willPathCastToBoolean(endPath);
 
       const rootParentPath = endPath.parentPath;
-      if (
-        rootParentPath.isUpdateExpression({ argument: node }) ||
-        rootParentPath.isAssignmentExpression({ left: node })
-      ) {
-        throw member.buildCodeFrameError(`can't handle assignment`);
+      if (rootParentPath.isUpdateExpression({ argument: node })) {
+        throw member.buildCodeFrameError(`can't handle update expression`);
       }
+      const isAssignment = rootParentPath.isAssignmentExpression({
+        left: endPath.node,
+      });
       const isDeleteOperation = rootParentPath.isUnaryExpression({
         operator: "delete",
       });
@@ -252,6 +252,9 @@ const handle = {
         parentPath.isUnaryExpression({ operator: "delete" })
       ) {
         parentPath.replaceWith(this.delete(member));
+      } else if (parentPath.isAssignmentExpression()) {
+        // `a?.#b = c` to `(a == null ? void 0 : a.#b = c)`
+        handleAssignment(this, member, parentPath);
       } else {
         member.replaceWith(this.get(member));
       }
@@ -295,7 +298,7 @@ const handle = {
       }
 
       let replacementPath: NodePath = endPath;
-      if (isDeleteOperation) {
+      if (isDeleteOperation || isAssignment) {
         replacementPath = endParentPath;
         regular = endParentPath.node;
       }
@@ -432,44 +435,7 @@ const handle = {
     // MEMBER += VALUE   ->   _set(MEMBER, _get(MEMBER) + VALUE)
     // MEMBER ??= VALUE   ->   _get(MEMBER) ?? _set(MEMBER, VALUE)
     if (parentPath.isAssignmentExpression({ left: node })) {
-      if (this.simpleSet) {
-        member.replaceWith(this.simpleSet(member));
-        return;
-      }
-
-      const { operator, right: value } = parentPath.node;
-
-      if (operator === "=") {
-        parentPath.replaceWith(this.set(member, value));
-      } else {
-        const operatorTrunc = operator.slice(0, -1);
-        if (LOGICAL_OPERATORS.includes(operatorTrunc)) {
-          // Give the state handler a chance to memoise the member, since we'll
-          // reference it twice. The first access (the get) should do the memo
-          // assignment.
-          this.memoise(member, 1);
-          parentPath.replaceWith(
-            logicalExpression(
-              operatorTrunc as t.LogicalExpression["operator"],
-              this.get(member),
-              this.set(member, value),
-            ),
-          );
-        } else {
-          // Here, the second access (the set) is evaluated first.
-          this.memoise(member, 2);
-          parentPath.replaceWith(
-            this.set(
-              member,
-              binaryExpression(
-                operatorTrunc as t.BinaryExpression["operator"],
-                this.get(member),
-                value,
-              ),
-            ),
-          );
-        }
-      }
+      handleAssignment(this, member, parentPath);
       return;
     }
 
@@ -549,6 +515,51 @@ const handle = {
   },
 };
 
+function handleAssignment(
+  state: HandlerState,
+  member: NodePath<t.MemberExpression | t.OptionalMemberExpression>,
+  parentPath: NodePath<t.AssignmentExpression>,
+) {
+  if (state.simpleSet) {
+    member.replaceWith(state.simpleSet(member));
+    return;
+  }
+
+  const { operator, right: value } = parentPath.node;
+
+  if (operator === "=") {
+    parentPath.replaceWith(state.set(member, value));
+  } else {
+    const operatorTrunc = operator.slice(0, -1);
+    if (LOGICAL_OPERATORS.includes(operatorTrunc)) {
+      // Give the state handler a chance to memoise the member, since we'll
+      // reference it twice. The first access (the get) should do the memo
+      // assignment.
+      state.memoise(member, 1);
+      parentPath.replaceWith(
+        logicalExpression(
+          operatorTrunc as t.LogicalExpression["operator"],
+          state.get(member),
+          state.set(member, value),
+        ),
+      );
+    } else {
+      // Here, the second access (the set) is evaluated first.
+      state.memoise(member, 2);
+      parentPath.replaceWith(
+        state.set(
+          member,
+          binaryExpression(
+            operatorTrunc as t.BinaryExpression["operator"],
+            state.get(member),
+            value,
+          ),
+        ),
+      );
+    }
+  }
+}
+
 export interface Handler<State> {
   memoise?(
     this: HandlerState<State> & State,

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/assumption-noDocumentAll/private-field-transformed/input.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+
+  method() {
+    obj?.#x = 1;
+    obj?.#x += 2;
+    obj?.#x ??= 3;
+    obj?.#x.y = 4;
+    obj?.#x.y += 5;
+    obj?.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/assumption-noDocumentAll/private-field-transformed/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["proposal-optional-chaining-assign", { "version": "2023-07" }],
+    "transform-class-properties"
+  ]
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/assumption-noDocumentAll/private-field-transformed/output.js

@@ -0,0 +1,18 @@
+var _x = /*#__PURE__*/new WeakMap();
+class A {
+  constructor() {
+    babelHelpers.classPrivateFieldInitSpec(this, _x, {
+      writable: true,
+      value: void 0
+    });
+  }
+  method() {
+    var _obj, _obj2, _obj3, _obj4, _obj5, _obj6;
+    (_obj = obj) == null ? void 0 : babelHelpers.classPrivateFieldSet(_obj, _x, 1);
+    (_obj2 = obj) == null ? void 0 : babelHelpers.classPrivateFieldSet(_obj2, _x, babelHelpers.classPrivateFieldGet(_obj2, _x) + 2);
+    (_obj3 = obj) == null ? void 0 : babelHelpers.classPrivateFieldGet(_obj3, _x) ?? babelHelpers.classPrivateFieldSet(_obj3, _x, 3);
+    (_obj4 = obj) == null ? void 0 : babelHelpers.classPrivateFieldGet(_obj4, _x).y = 4;
+    (_obj5 = obj) == null ? void 0 : babelHelpers.classPrivateFieldGet(_obj5, _x).y += 5;
+    (_obj6 = obj) == null ? void 0 : babelHelpers.classPrivateFieldGet(_obj6, _x).y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/assumption-noDocumentAll/private-field/input.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+
+  method() {
+    obj?.#x = 1;
+    obj?.#x += 2;
+    obj?.#x ??= 3;
+    obj?.#x.y = 4;
+    obj?.#x.y += 5;
+    obj?.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/assumption-noDocumentAll/private-field/output.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+  method() {
+    var _obj, _obj2, _obj3, _obj4, _obj5, _obj6;
+    (_obj = obj) == null ? void 0 : _obj.#x = 1;
+    (_obj2 = obj) == null ? void 0 : _obj2.#x += 2;
+    (_obj3 = obj) == null ? void 0 : _obj3.#x ??= 3;
+    (_obj4 = obj) == null ? void 0 : _obj4.#x.y = 4;
+    (_obj5 = obj) == null ? void 0 : _obj5.#x.y += 5;
+    (_obj6 = obj) == null ? void 0 : _obj6.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed-privateFieldsAsProperties/input.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+
+  method() {
+    obj?.#x = 1;
+    obj?.#x += 2;
+    obj?.#x ??= 3;
+    obj?.#x.y = 4;
+    obj?.#x.y += 5;
+    obj?.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed-privateFieldsAsProperties/options.json

@@ -0,0 +1,9 @@
+{
+  "plugins": [
+    ["proposal-optional-chaining-assign", { "version": "2023-07" }],
+    "transform-class-properties"
+  ],
+  "assumptions": {
+    "privateFieldsAsProperties": true
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed-privateFieldsAsProperties/output.js

@@ -0,0 +1,18 @@
+var _x = /*#__PURE__*/babelHelpers.classPrivateFieldLooseKey("x");
+class A {
+  constructor() {
+    Object.defineProperty(this, _x, {
+      writable: true,
+      value: void 0
+    });
+  }
+  method() {
+    var _obj, _obj2, _obj3, _obj4, _obj5, _obj6;
+    (_obj = obj) === null || _obj === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj, _x)[_x] = 1;
+    (_obj2 = obj) === null || _obj2 === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj2, _x)[_x] += 2;
+    (_obj3 = obj) === null || _obj3 === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj3, _x)[_x] ??= 3;
+    (_obj4 = obj) === null || _obj4 === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj4, _x)[_x].y = 4;
+    (_obj5 = obj) === null || _obj5 === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj5, _x)[_x].y += 5;
+    (_obj6 = obj) === null || _obj6 === void 0 ? void 0 : babelHelpers.classPrivateFieldLooseBase(_obj6, _x)[_x].y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed/input.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+
+  method() {
+    obj?.#x = 1;
+    obj?.#x += 2;
+    obj?.#x ??= 3;
+    obj?.#x.y = 4;
+    obj?.#x.y += 5;
+    obj?.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed/options.json

@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    ["proposal-optional-chaining-assign", { "version": "2023-07" }],
+    "transform-class-properties"
+  ]
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field-transformed/output.js

@@ -0,0 +1,18 @@
+var _x = /*#__PURE__*/new WeakMap();
+class A {
+  constructor() {
+    babelHelpers.classPrivateFieldInitSpec(this, _x, {
+      writable: true,
+      value: void 0
+    });
+  }
+  method() {
+    var _obj, _obj2, _obj3, _obj4, _obj5, _obj6;
+    (_obj = obj) === null || _obj === void 0 ? void 0 : babelHelpers.classPrivateFieldSet(_obj, _x, 1);
+    (_obj2 = obj) === null || _obj2 === void 0 ? void 0 : babelHelpers.classPrivateFieldSet(_obj2, _x, babelHelpers.classPrivateFieldGet(_obj2, _x) + 2);
+    (_obj3 = obj) === null || _obj3 === void 0 ? void 0 : babelHelpers.classPrivateFieldGet(_obj3, _x) ?? babelHelpers.classPrivateFieldSet(_obj3, _x, 3);
+    (_obj4 = obj) === null || _obj4 === void 0 ? void 0 : babelHelpers.classPrivateFieldGet(_obj4, _x).y = 4;
+    (_obj5 = obj) === null || _obj5 === void 0 ? void 0 : babelHelpers.classPrivateFieldGet(_obj5, _x).y += 5;
+    (_obj6 = obj) === null || _obj6 === void 0 ? void 0 : babelHelpers.classPrivateFieldGet(_obj6, _x).y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field/input.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+
+  method() {
+    obj?.#x = 1;
+    obj?.#x += 2;
+    obj?.#x ??= 3;
+    obj?.#x.y = 4;
+    obj?.#x.y += 5;
+    obj?.#x.y ??= 6;
+  }
+}

packages/babel-plugin-proposal-optional-chaining-assign/test/fixtures/general/private-field/output.js

@@ -0,0 +1,12 @@
+class A {
+  #x;
+  method() {
+    var _obj, _obj2, _obj3, _obj4, _obj5, _obj6;
+    (_obj = obj) === null || _obj === void 0 ? void 0 : _obj.#x = 1;
+    (_obj2 = obj) === null || _obj2 === void 0 ? void 0 : _obj2.#x += 2;
+    (_obj3 = obj) === null || _obj3 === void 0 ? void 0 : _obj3.#x ??= 3;
+    (_obj4 = obj) === null || _obj4 === void 0 ? void 0 : _obj4.#x.y = 4;
+    (_obj5 = obj) === null || _obj5 === void 0 ? void 0 : _obj5.#x.y += 5;
+    (_obj6 = obj) === null || _obj6 === void 0 ? void 0 : _obj6.#x.y ??= 6;
+  }
+}