Private Class Methods Stage 3: Private Accessors (#9101)

* Add accessor loose support

* Add private accessors spec support

* Fix private dupe name check

* Changes from code review

* Add duplicated names tests

* Add get/set-only tests

* Move accessors tests

* Split out updates tests

* Add helper change tests

* Update test output

* Update test options

packages/babel-helper-create-class-features-plugin/src/features.js

@@ -72,12 +72,6 @@ export function verifyUsedFeatures(path, file) {
         "@babel/plugin-class-features doesn't support class static private methods yet.",
       );
     }
-
-    if (path.node.kind !== "method") {
-      throw path.buildCodeFrameError(
-        "@babel/plugin-class-features doesn't support class private accessors yet.",
-      );
-    }
   }
 
   if (

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

@@ -6,16 +6,26 @@ import optimiseCall from "@babel/helper-optimise-call-expression";
 export function buildPrivateNamesMap(props) {
   const privateNamesMap = new Map();
   for (const prop of props) {
-    if (prop.isPrivate()) {
+    const isPrivate = prop.isPrivate();
+    const isMethod = !prop.isProperty();
+    const isInstance = !prop.node.static;
+    if (isPrivate) {
       const { name } = prop.node.key.id;
-      privateNamesMap.set(name, {
-        id: prop.scope.generateUidIdentifier(name),
-        static: !!prop.node.static,
-        method: prop.isMethod(),
-        methodId: prop.isMethod()
-          ? prop.scope.generateUidIdentifier(name)
-          : undefined,
-      });
+      const update = privateNamesMap.has(name)
+        ? privateNamesMap.get(name)
+        : {
+            id: prop.scope.generateUidIdentifier(name),
+            static: !isInstance,
+            method: isMethod,
+          };
+      if (prop.node.kind === "get") {
+        update.getId = prop.scope.generateUidIdentifier(`get_${name}`);
+      } else if (prop.node.kind === "set") {
+        update.setId = prop.scope.generateUidIdentifier(`set_${name}`);
+      } else if (prop.node.kind === "method" && isMethod && isInstance) {
+        update.methodId = prop.scope.generateUidIdentifier(name);
+      }
+      privateNamesMap.set(name, update);
     }
   }
   return privateNamesMap;
@@ -31,7 +41,7 @@ export function buildPrivateNamesNodes(privateNamesMap, loose, state) {
     // In spec mode, only instance fields need a "private name" initializer
     // because static fields are directly assigned to a variable in the
     // buildPrivateStaticFieldInitSpec function.
-    const { id, static: isStatic, method: isMethod } = value;
+    const { id, static: isStatic, method: isMethod, getId, setId } = value;
     if (loose) {
       initNodes.push(
         template.statement.ast`
@@ -39,7 +49,11 @@ export function buildPrivateNamesNodes(privateNamesMap, loose, state) {
         `,
       );
     } else if (isMethod && !isStatic) {
-      initNodes.push(template.statement.ast`var ${id} = new WeakSet();`);
+      if (getId || setId) {
+        initNodes.push(template.statement.ast`var ${id} = new WeakMap();`);
+      } else {
+        initNodes.push(template.statement.ast`var ${id} = new WeakSet();`);
+      }
     } else if (!isStatic) {
       initNodes.push(template.statement.ast`var ${id} = new WeakMap();`);
     }
@@ -121,6 +135,8 @@ const privateNameHandlerSpec = {
       static: isStatic,
       method: isMethod,
       methodId,
+      getId,
+      setId,
     } = privateNamesMap.get(name);
 
     if (isStatic && !isMethod) {
@@ -128,41 +144,57 @@ const privateNameHandlerSpec = {
         file.addHelper("classStaticPrivateFieldSpecGet"),
         [this.receiver(member), t.cloneNode(classRef), t.cloneNode(id)],
       );
-    } else if (isMethod) {
+    }
+    if (isMethod) {
+      if (getId || setId) {
+        return t.callExpression(file.addHelper("classPrivateFieldGet"), [
+          this.receiver(member),
+          t.cloneNode(id),
+        ]);
+      }
       return t.callExpression(file.addHelper("classPrivateMethodGet"), [
         this.receiver(member),
         t.cloneNode(id),
         t.cloneNode(methodId),
       ]);
-    } else {
-      return t.callExpression(file.addHelper("classPrivateFieldGet"), [
-        this.receiver(member),
-        t.cloneNode(id),
-      ]);
     }
+    return t.callExpression(file.addHelper("classPrivateFieldGet"), [
+      this.receiver(member),
+      t.cloneNode(id),
+    ]);
   },
 
   set(member, value) {
     const { classRef, privateNamesMap, file } = this;
     const { name } = member.node.property.id;
-    const { id, static: isStatic, method: isMethod } = privateNamesMap.get(
-      name,
-    );
+    const {
+      id,
+      static: isStatic,
+      method: isMethod,
+      setId,
+    } = privateNamesMap.get(name);
 
     if (isStatic && !isMethod) {
       return t.callExpression(
         file.addHelper("classStaticPrivateFieldSpecSet"),
         [this.receiver(member), t.cloneNode(classRef), t.cloneNode(id), value],
       );
-    } else if (isMethod) {
-      return t.callExpression(file.addHelper("classPrivateMethodSet"), []);
-    } else {
-      return t.callExpression(file.addHelper("classPrivateFieldSet"), [
-        this.receiver(member),
-        t.cloneNode(id),
-        value,
-      ]);
     }
+    if (isMethod) {
+      if (setId) {
+        return t.callExpression(file.addHelper("classPrivateFieldSet"), [
+          this.receiver(member),
+          t.cloneNode(id),
+          value,
+        ]);
+      }
+      return t.callExpression(file.addHelper("classPrivateMethodSet"), []);
+    }
+    return t.callExpression(file.addHelper("classPrivateFieldSet"), [
+      this.receiver(member),
+      t.cloneNode(id),
+      value,
+    ]);
   },
 
   call(member, args) {
@@ -255,21 +287,91 @@ function buildPrivateStaticFieldInitSpec(prop, privateNamesMap) {
 }
 
 function buildPrivateMethodInitLoose(ref, prop, privateNamesMap) {
-  const { methodId, id } = privateNamesMap.get(prop.node.key.id.name);
+  const privateName = privateNamesMap.get(prop.node.key.id.name);
+  const { methodId, id, getId, setId, initAdded } = privateName;
+  if (initAdded) return;
 
-  return template.statement.ast`
-    Object.defineProperty(${ref}, ${id}, {
-      // configurable is false by default
-      // enumerable is false by default
-      // writable is false by default
-      value: ${methodId.name}
+  if (methodId) {
+    return template.statement.ast`
+        Object.defineProperty(${ref}, ${id}, {
+          // configurable is false by default
+          // enumerable is false by default
+          // writable is false by default
+          value: ${methodId.name}
+        });
+      `;
+  }
+
+  if (getId || setId) {
+    privateNamesMap.set(prop.node.key.id.name, {
+      ...privateName,
+      initAdded: true,
     });
-  `;
+
+    if (getId && setId) {
+      return template.statement.ast`
+        Object.defineProperty(${ref}, ${id}, {
+          // configurable is false by default
+          // enumerable is false by default
+          // writable is false by default
+          get: ${getId.name},
+          set: ${setId.name}
+        });
+      `;
+    } else if (getId && !setId) {
+      return template.statement.ast`
+        Object.defineProperty(${ref}, ${id}, {
+          // configurable is false by default
+          // enumerable is false by default
+          // writable is false by default
+          get: ${getId.name}
+        });
+      `;
+    } else if (!getId && setId) {
+      return template.statement.ast`
+        Object.defineProperty(${ref}, ${id}, {
+          // configurable is false by default
+          // enumerable is false by default
+          // writable is false by default
+          set: ${setId.name}
+        });
+      `;
+    }
+  }
 }
 
 function buildPrivateInstanceMethodInitSpec(ref, prop, privateNamesMap) {
-  const { id } = privateNamesMap.get(prop.node.key.id.name);
+  const privateName = privateNamesMap.get(prop.node.key.id.name);
+  const { id, getId, setId, initAdded } = privateName;
+  if (initAdded) return;
 
+  if (getId || setId) {
+    privateNamesMap.set(prop.node.key.id.name, {
+      ...privateName,
+      initAdded: true,
+    });
+
+    if (getId && setId) {
+      return template.statement.ast`
+        ${id}.set(${ref}, {
+          get: ${getId.name},
+          set: ${setId.name}
+        });
+      `;
+    } else if (getId && !setId) {
+      return template.statement.ast`
+        ${id}.set(${ref}, {
+          get: ${getId.name}
+        });
+      `;
+    } else if (!getId && setId) {
+      return template.statement.ast`
+        ${id}.set(${ref}, {
+          set: ${setId.name}
+        });
+      `;
+    }
+  }
   return template.statement.ast`${id}.add(${ref})`;
 }
 
@@ -300,9 +402,37 @@ function buildPublicFieldInitSpec(ref, prop, state) {
 }
 
 function buildPrivateInstanceMethodDeclaration(prop, privateNamesMap) {
-  const { methodId } = privateNamesMap.get(prop.node.key.id.name);
+  const privateName = privateNamesMap.get(prop.node.key.id.name);
+  const {
+    methodId,
+    getId,
+    setId,
+    getterDeclared,
+    setterDeclared,
+  } = privateName;
   const { params, body } = prop.node;
   const methodValue = t.functionExpression(methodId, params, body);
+  const isGetter = getId && !getterDeclared && params.length === 0;
+  const isSetter = setId && !setterDeclared && params.length > 0;
+
+  if (isGetter) {
+    privateNamesMap.set(prop.node.key.id.name, {
+      ...privateName,
+      getterDeclared: true,
+    });
+    return t.variableDeclaration("var", [
+      t.variableDeclarator(getId, methodValue),
+    ]);
+  }
+  if (isSetter) {
+    privateNamesMap.set(prop.node.key.id.name, {
+      ...privateName,
+      setterDeclared: true,
+    });
+    return t.variableDeclaration("var", [
+      t.variableDeclarator(setId, methodValue),
+    ]);
+  }
 
   return t.variableDeclaration("var", [
     t.variableDeclarator(methodId, methodValue),
@@ -404,7 +534,7 @@ export function buildFieldsInitNodes(
 
   return {
     staticNodes,
-    instanceNodes,
+    instanceNodes: instanceNodes.filter(Boolean),
     wrapClass(path) {
       for (const prop of props) {
         prop.remove();

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

@@ -75,11 +75,39 @@ export function createClassFeaturePlugin({
 
           if (path.isPrivate()) {
             const { name } = path.node.key.id;
+            const getName = `get ${name}`;
+            const setName = `set ${name}`;
 
-            if (privateNames.has(name)) {
-              throw path.buildCodeFrameError("Duplicate private field");
+            if (path.node.kind === "get") {
+              if (
+                privateNames.has(getName) ||
+                (privateNames.has(name) && !privateNames.has(setName))
+              ) {
+                throw path.buildCodeFrameError("Duplicate private field");
+              }
+
+              privateNames.add(getName).add(name);
+            } else if (path.node.kind === "set") {
+              if (
+                privateNames.has(setName) ||
+                (privateNames.has(name) && !privateNames.has(getName))
+              ) {
+                throw path.buildCodeFrameError("Duplicate private field");
+              }
+
+              privateNames.add(setName).add(name);
+            } else {
+              if (
+                (privateNames.has(name) &&
+                  (!privateNames.has(getName) && !privateNames.has(setName))) ||
+                (privateNames.has(name) &&
+                  (privateNames.has(getName) || privateNames.has(setName)))
+              ) {
+                throw path.buildCodeFrameError("Duplicate private field");
+              }
+
+              privateNames.add(name);
             }
-            privateNames.add(name);
           }
 
           if (path.isClassMethod({ kind: "constructor" })) {

packages/babel-helpers/src/helpers.js

@@ -1052,7 +1052,11 @@ helpers.classPrivateFieldGet = helper("7.0.0-beta.0")`
     if (!privateMap.has(receiver)) {
       throw new TypeError("attempted to get private field on non-instance");
     }
-    return privateMap.get(receiver).value;
+    var descriptor = privateMap.get(receiver);
+    if (descriptor.get) {
+      return descriptor.get.call(receiver);
+    }
+    return descriptor.value;
   }
 `;
 
@@ -1062,13 +1066,19 @@ helpers.classPrivateFieldSet = helper("7.0.0-beta.0")`
       throw new TypeError("attempted to set private field on non-instance");
     }
     var descriptor = privateMap.get(receiver);
-    if (!descriptor.writable) {
-      // This should only throw in strict mode, but class bodies are
-      // always strict and private fields can only be used inside
-      // class bodies.
-      throw new TypeError("attempted to set read only private field");
+    if (descriptor.set) {
+      descriptor.set.call(receiver, value);
+    } else {
+      if (!descriptor.writable) {
+        // This should only throw in strict mode, but class bodies are
+        // always strict and private fields can only be used inside
+        // class bodies.
+        throw new TypeError("attempted to set read only private field");
+      }
+
+      descriptor.value = value;
     }
-    descriptor.value = value;
+
     return value;
   }
 `;

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/basic/exec.js

@@ -0,0 +1,31 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+}
+
+const cl = new Cl();
+
+expect(cl.publicGetPrivateField()).toEqual("top secret string");
+
+cl.publicSetPrivateField("new secret string");
+expect(cl.publicGetPrivateField()).toEqual("new secret string");
+

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/basic/input.js

@@ -0,0 +1,23 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/basic/output.js

@@ -0,0 +1,43 @@
+var Cl =
+/*#__PURE__*/
+function () {
+  "use strict";
+
+  function Cl() {
+    babelHelpers.classCallCheck(this, Cl);
+    Object.defineProperty(this, _privateFieldValue, {
+      get: _get_privateFieldValue,
+      set: _set_privateFieldValue
+    });
+    Object.defineProperty(this, _privateField, {
+      writable: true,
+      value: "top secret string"
+    });
+    this.publicField = "not secret string";
+  }
+
+  babelHelpers.createClass(Cl, [{
+    key: "publicGetPrivateField",
+    value: function publicGetPrivateField() {
+      return babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue];
+    }
+  }, {
+    key: "publicSetPrivateField",
+    value: function publicSetPrivateField(newValue) {
+      babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] = newValue;
+    }
+  }]);
+  return Cl;
+}();
+
+var _privateField = babelHelpers.classPrivateFieldLooseKey("privateField");
+
+var _privateFieldValue = babelHelpers.classPrivateFieldLooseKey("privateFieldValue");
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField];
+};
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField] = newValue;
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/get-only-setter/exec.js

@@ -0,0 +1,13 @@
+class Cl {
+  #privateField = 0;
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  constructor() {
+    expect(this.#privateFieldValue).toBeUndefined();
+  }
+}
+
+const cl = new Cl();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/get-only-setter/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  constructor() {
+    this.publicField = this.#privateFieldValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/get-only-setter/output.js

@@ -0,0 +1,21 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+  Object.defineProperty(this, _privateFieldValue, {
+    set: _set_privateFieldValue
+  });
+  Object.defineProperty(this, _privateField, {
+    writable: true,
+    value: 0
+  });
+  this.publicField = babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue];
+};
+
+var _privateField = babelHelpers.classPrivateFieldLooseKey("privateField");
+
+var _privateFieldValue = babelHelpers.classPrivateFieldLooseKey("privateFieldValue");
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField] = newValue;
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/helper/exec.js

@@ -0,0 +1,11 @@
+let foo;
+class Cl {
+  set #foo(v) { return 1 }
+  test() {
+    foo = this.#foo = 2;
+  }
+}
+
+new Cl().test();
+
+expect(foo).toBe(2);

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/options.json

@@ -0,0 +1,15 @@
+{
+  "plugins": [
+    [
+      "external-helpers",
+      {
+        "helperVersion": "7.1000.0"
+      }
+    ],
+    ["proposal-private-methods", { "loose": true }],
+    ["proposal-class-properties", { "loose": true }],
+    "transform-classes",
+    "transform-block-scoping",
+    "syntax-class-properties"
+  ]
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/set-only-getter/exec.js

@@ -0,0 +1,13 @@
+class Cl {
+  #privateField = 0;
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  constructor() {
+    expect(() => this.#privateFieldValue = 1).toThrow(TypeError);
+  }
+}
+
+const cl = new Cl();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/set-only-getter/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  constructor() {
+    this.#privateFieldValue = 1;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/set-only-getter/output.js

@@ -0,0 +1,21 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+  Object.defineProperty(this, _privateFieldValue, {
+    get: _get_privateFieldValue
+  });
+  Object.defineProperty(this, _privateField, {
+    writable: true,
+    value: 0
+  });
+  babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] = 1;
+};
+
+var _privateField = babelHelpers.classPrivateFieldLooseKey("privateField");
+
+var _privateFieldValue = babelHelpers.classPrivateFieldLooseKey("privateFieldValue");
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField];
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/updates/exec.js

@@ -0,0 +1,50 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+
+  get publicFieldValue() {
+    return this.publicField;
+  }
+
+  set publicFieldValue(newValue) {
+    this.publicField = newValue;
+  }
+
+  testUpdates() {
+    this.#privateField = 0;
+    this.publicField = 0;
+    this.#privateFieldValue = this.#privateFieldValue++;
+    this.publicFieldValue = this.publicFieldValue++;
+    expect(this.#privateField).toEqual(this.publicField);
+
+    ++this.#privateFieldValue;
+    ++this.publicFieldValue;
+    expect(this.#privateField).toEqual(this.publicField);
+
+    this.#privateFieldValue += 1;
+    this.publicFieldValue += 1;
+    expect(this.#privateField).toEqual(this.publicField);
+  }
+}
+
+const cl = new Cl();
+cl.testUpdates();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/updates/input.js

@@ -0,0 +1,47 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+
+  get publicFieldValue() {
+    return this.publicField;
+  }
+
+  set publicFieldValue(newValue) {
+    this.publicField = newValue;
+  }
+
+  testUpdates() {
+    this.#privateField = 0;
+    this.publicField = 0;
+    this.#privateFieldValue = this.#privateFieldValue++;
+    this.publicFieldValue = this.publicFieldValue++;
+
+    ++this.#privateFieldValue;
+    ++this.publicFieldValue;
+
+    this.#privateFieldValue += 1;
+    this.publicFieldValue += 1;
+
+    this.#privateFieldValue = -(this.#privateFieldValue ** this.#privateFieldValue);
+    this.publicFieldValue = -(this.publicFieldValue ** this.publicFieldValue);
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors-loose/updates/output.js

@@ -0,0 +1,65 @@
+var Cl =
+/*#__PURE__*/
+function () {
+  "use strict";
+
+  function Cl() {
+    babelHelpers.classCallCheck(this, Cl);
+    Object.defineProperty(this, _privateFieldValue, {
+      get: _get_privateFieldValue,
+      set: _set_privateFieldValue
+    });
+    Object.defineProperty(this, _privateField, {
+      writable: true,
+      value: "top secret string"
+    });
+    this.publicField = "not secret string";
+  }
+
+  babelHelpers.createClass(Cl, [{
+    key: "publicGetPrivateField",
+    value: function publicGetPrivateField() {
+      return babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue];
+    }
+  }, {
+    key: "publicSetPrivateField",
+    value: function publicSetPrivateField(newValue) {
+      babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] = newValue;
+    }
+  }, {
+    key: "testUpdates",
+    value: function testUpdates() {
+      babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField] = 0;
+      this.publicField = 0;
+      babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] = babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue]++;
+      this.publicFieldValue = this.publicFieldValue++;
+      ++babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue];
+      ++this.publicFieldValue;
+      babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] += 1;
+      this.publicFieldValue += 1;
+      babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] = -(babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue] ** babelHelpers.classPrivateFieldLooseBase(this, _privateFieldValue)[_privateFieldValue]);
+      this.publicFieldValue = -(this.publicFieldValue ** this.publicFieldValue);
+    }
+  }, {
+    key: "publicFieldValue",
+    get: function () {
+      return this.publicField;
+    },
+    set: function (newValue) {
+      this.publicField = newValue;
+    }
+  }]);
+  return Cl;
+}();
+
+var _privateField = babelHelpers.classPrivateFieldLooseKey("privateField");
+
+var _privateFieldValue = babelHelpers.classPrivateFieldLooseKey("privateFieldValue");
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField];
+};
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldLooseBase(this, _privateField)[_privateField] = newValue;
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/basic/exec.js

@@ -0,0 +1,31 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+}
+
+const cl = new Cl();
+
+expect(cl.publicGetPrivateField()).toEqual("top secret string");
+
+cl.publicSetPrivateField("new secret string");
+expect(cl.publicGetPrivateField()).toEqual("new secret string");
+

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/basic/input.js

@@ -0,0 +1,23 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/basic/output.js

@@ -0,0 +1,46 @@
+var Cl =
+/*#__PURE__*/
+function () {
+  "use strict";
+
+  function Cl() {
+    babelHelpers.classCallCheck(this, Cl);
+
+    _privateFieldValue.set(this, {
+      get: _get_privateFieldValue,
+      set: _set_privateFieldValue
+    });
+
+    _privateField.set(this, {
+      writable: true,
+      value: "top secret string"
+    });
+
+    this.publicField = "not secret string";
+  }
+
+  babelHelpers.createClass(Cl, [{
+    key: "publicGetPrivateField",
+    value: function publicGetPrivateField() {
+      return babelHelpers.classPrivateFieldGet(this, _privateFieldValue);
+    }
+  }, {
+    key: "publicSetPrivateField",
+    value: function publicSetPrivateField(newValue) {
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, newValue);
+    }
+  }]);
+  return Cl;
+}();
+
+var _privateField = new WeakMap();
+
+var _privateFieldValue = new WeakMap();
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldGet(this, _privateField);
+};
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldSet(this, _privateField, newValue);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/get-only-setter/exec.js

@@ -0,0 +1,13 @@
+class Cl {
+  #privateField = 0;
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  constructor() {
+    expect(this.#privateFieldValue).toBeUndefined();
+  }
+}
+
+const cl = new Cl();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/get-only-setter/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  constructor() {
+    this.publicField = this.#privateFieldValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/get-only-setter/output.js

@@ -0,0 +1,24 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+
+  _privateFieldValue.set(this, {
+    set: _set_privateFieldValue
+  });
+
+  _privateField.set(this, {
+    writable: true,
+    value: 0
+  });
+
+  this.publicField = babelHelpers.classPrivateFieldGet(this, _privateFieldValue);
+};
+
+var _privateField = new WeakMap();
+
+var _privateFieldValue = new WeakMap();
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldSet(this, _privateField, newValue);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/helper/exec.js

@@ -0,0 +1,11 @@
+let foo;
+class Cl {
+  set #foo(v) { return 1 }
+  test() {
+    foo = this.#foo = 2;
+  }
+}
+
+new Cl().test();
+
+expect(foo).toBe(2);

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/options.json

@@ -0,0 +1,15 @@
+{
+  "plugins": [
+    [
+      "external-helpers",
+      {
+        "helperVersion": "7.1000.0"
+      }
+    ],
+    "proposal-private-methods",
+    "proposal-class-properties",
+    "transform-classes",
+    "transform-block-scoping",
+    "syntax-class-properties"
+  ]
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/set-only-getter/exec.js

@@ -0,0 +1,13 @@
+class Cl {
+  #privateField = 0;
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  constructor() {
+    expect(() => this.#privateFieldValue = 1).toThrow(TypeError);
+  }
+}
+
+const cl = new Cl();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/set-only-getter/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  constructor() {
+    this.#privateFieldValue = 1;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/set-only-getter/output.js

@@ -0,0 +1,24 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+
+  _privateFieldValue.set(this, {
+    get: _get_privateFieldValue
+  });
+
+  _privateField.set(this, {
+    writable: true,
+    value: 0
+  });
+
+  babelHelpers.classPrivateMethodSet();
+};
+
+var _privateField = new WeakMap();
+
+var _privateFieldValue = new WeakMap();
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldGet(this, _privateField);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/updates/exec.js

@@ -0,0 +1,50 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+
+  get publicFieldValue() {
+    return this.publicField;
+  }
+
+  set publicFieldValue(newValue) {
+    this.publicField = newValue;
+  }
+
+  testUpdates() {
+    this.#privateField = 0;
+    this.publicField = 0;
+    this.#privateFieldValue = this.#privateFieldValue++;
+    this.publicFieldValue = this.publicFieldValue++;
+    expect(this.#privateField).toEqual(this.publicField);
+
+    ++this.#privateFieldValue;
+    ++this.publicFieldValue;
+    expect(this.#privateField).toEqual(this.publicField);
+
+    this.#privateFieldValue += 1;
+    this.publicFieldValue += 1;
+    expect(this.#privateField).toEqual(this.publicField);
+  }
+}
+
+const cl = new Cl();
+cl.testUpdates();

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/updates/input.js

@@ -0,0 +1,47 @@
+class Cl {
+  #privateField = "top secret string";
+
+  constructor() {
+    this.publicField = "not secret string";
+  }
+
+  get #privateFieldValue() {
+    return this.#privateField;
+  }
+
+  set #privateFieldValue(newValue) {
+    this.#privateField = newValue;
+  }
+
+  publicGetPrivateField() {
+    return this.#privateFieldValue;
+  }
+
+  publicSetPrivateField(newValue) {
+    this.#privateFieldValue = newValue;
+  }
+
+  get publicFieldValue() {
+    return this.publicField;
+  }
+
+  set publicFieldValue(newValue) {
+    this.publicField = newValue;
+  }
+
+  testUpdates() {
+    this.#privateField = 0;
+    this.publicField = 0;
+    this.#privateFieldValue = this.#privateFieldValue++;
+    this.publicFieldValue = this.publicFieldValue++;
+
+    ++this.#privateFieldValue;
+    ++this.publicFieldValue;
+
+    this.#privateFieldValue += 1;
+    this.publicFieldValue += 1;
+
+    this.#privateFieldValue = -(this.#privateFieldValue ** this.#privateFieldValue);
+    this.publicFieldValue = -(this.publicFieldValue ** this.publicFieldValue);
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/accessors/updates/output.js

@@ -0,0 +1,70 @@
+var Cl =
+/*#__PURE__*/
+function () {
+  "use strict";
+
+  function Cl() {
+    babelHelpers.classCallCheck(this, Cl);
+
+    _privateFieldValue.set(this, {
+      get: _get_privateFieldValue,
+      set: _set_privateFieldValue
+    });
+
+    _privateField.set(this, {
+      writable: true,
+      value: "top secret string"
+    });
+
+    this.publicField = "not secret string";
+  }
+
+  babelHelpers.createClass(Cl, [{
+    key: "publicGetPrivateField",
+    value: function publicGetPrivateField() {
+      return babelHelpers.classPrivateFieldGet(this, _privateFieldValue);
+    }
+  }, {
+    key: "publicSetPrivateField",
+    value: function publicSetPrivateField(newValue) {
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, newValue);
+    }
+  }, {
+    key: "testUpdates",
+    value: function testUpdates() {
+      var _this$privateFieldVal, _this$privateFieldVal2;
+
+      babelHelpers.classPrivateFieldSet(this, _privateField, 0);
+      this.publicField = 0;
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, (babelHelpers.classPrivateFieldSet(this, _privateFieldValue, (_this$privateFieldVal2 = +babelHelpers.classPrivateFieldGet(this, _privateFieldValue)) + 1), _this$privateFieldVal2));
+      this.publicFieldValue = this.publicFieldValue++;
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, +babelHelpers.classPrivateFieldGet(this, _privateFieldValue) + 1);
+      ++this.publicFieldValue;
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, babelHelpers.classPrivateFieldGet(this, _privateFieldValue) + 1);
+      this.publicFieldValue += 1;
+      babelHelpers.classPrivateFieldSet(this, _privateFieldValue, -(babelHelpers.classPrivateFieldGet(this, _privateFieldValue) ** babelHelpers.classPrivateFieldGet(this, _privateFieldValue)));
+      this.publicFieldValue = -(this.publicFieldValue ** this.publicFieldValue);
+    }
+  }, {
+    key: "publicFieldValue",
+    get: function () {
+      return this.publicField;
+    },
+    set: function (newValue) {
+      this.publicField = newValue;
+    }
+  }]);
+  return Cl;
+}();
+
+var _privateField = new WeakMap();
+
+var _privateFieldValue = new WeakMap();
+
+var _get_privateFieldValue = function () {
+  return babelHelpers.classPrivateFieldGet(this, _privateField);
+};
+
+var _set_privateFieldValue = function (newValue) {
+  babelHelpers.classPrivateFieldSet(this, _privateField, newValue);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-get/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+  
+  get #getSet() {
+    return this.#privateField;
+  }
+
+  get #getSet() {
+    return this.#privateField;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-get/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-method/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+  
+  get #foo() {
+    return this.#privateField;
+  }
+
+  #foo() {
+    return 'foo';
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-method/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-set/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  get #getSet() {
+    return this.#privateField;
+  }
+  
+  set #getSet(newValue) {
+    this.#privateField = newValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/get-set/output.js

@@ -0,0 +1,27 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+
+  _getSet.set(this, {
+    get: _get_getSet,
+    set: _set_getSet
+  });
+
+  _privateField.set(this, {
+    writable: true,
+    value: 0
+  });
+};
+
+var _privateField = new WeakMap();
+
+var _getSet = new WeakMap();
+
+var _get_getSet = function () {
+  return babelHelpers.classPrivateFieldGet(this, _privateField);
+};
+
+var _set_getSet = function (newValue) {
+  babelHelpers.classPrivateFieldSet(this, _privateField, newValue);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-get/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  #foo() {
+    return 'foo';
+  }
+
+  get #foo() {
+    return this.#privateField;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-get/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-method/input.js

@@ -0,0 +1,10 @@
+class Cl {
+  #dank() {
+    return 'foo';
+  }
+
+  #dank() {
+    return 'foo';
+  }
+
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-method/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-set/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  #foo() {
+    return 'foo';
+  }
+
+  set #foo(newValue) {
+    this.#privateField = newValue;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/method-set/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/options.json

@@ -0,0 +1,15 @@
+{
+  "plugins": [
+    [
+      "external-helpers",
+      {
+        "helperVersion": "7.1000.0"
+      }
+    ],
+    "proposal-private-methods",
+    "proposal-class-properties",
+    "transform-classes",
+    "transform-block-scoping",
+    "syntax-class-properties"
+  ]
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-get/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+  
+  set #getSet(newValue) {
+    this.#privateField = newValue;
+  }
+
+  get #getSet() {
+    return this.#privateField;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-get/output.js

@@ -0,0 +1,27 @@
+var Cl = function Cl() {
+  "use strict";
+
+  babelHelpers.classCallCheck(this, Cl);
+
+  _getSet.set(this, {
+    get: _get_getSet,
+    set: _set_getSet
+  });
+
+  _privateField.set(this, {
+    writable: true,
+    value: 0
+  });
+};
+
+var _privateField = new WeakMap();
+
+var _getSet = new WeakMap();
+
+var _set_getSet = function (newValue) {
+  babelHelpers.classPrivateFieldSet(this, _privateField, newValue);
+};
+
+var _get_getSet = function () {
+  return babelHelpers.classPrivateFieldGet(this, _privateField);
+};

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-method/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+
+  set #foo(newValue) {
+    this.#privateField = newValue;
+  }
+
+  #foo() {
+    return 'foo';
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-method/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-set/input.js

@@ -0,0 +1,11 @@
+class Cl {
+  #privateField = 0;
+  
+  set #getSet(newValue) {
+    return this.#privateField;
+  }
+
+  set #getSet(newValue) {
+    return this.#privateField;
+  }
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/duplicated-names/set-set/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Duplicate private field"
+}

packages/babel-plugin-proposal-private-methods/test/fixtures/private-method-loose/options.json

@@ -3,7 +3,7 @@
     [
       "external-helpers",
       {
-        "helperVersion": "7.1.6"
+        "helperVersion": "7.1000.0"
       }
     ],
     ["proposal-private-methods", { "loose": true }],

packages/babel-plugin-proposal-private-methods/test/fixtures/private-method/options.json

@@ -3,7 +3,7 @@
     [
       "external-helpers",
       {
-        "helperVersion": "7.1.6"
+        "helperVersion": "7.1000.0"
       }
     ],
     "proposal-private-methods",