[WIP] Private static accessors strict

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

@@ -142,9 +142,10 @@ const privateNameHandlerSpec = {
     } = privateNamesMap.get(name);
 
     if (isStatic) {
-      const helperName = isMethod
-        ? "classStaticPrivateMethodGet"
-        : "classStaticPrivateFieldSpecGet";
+      const helperName =
+        isMethod && !(getId || setId)
+          ? "classStaticPrivateMethodGet"
+          : "classStaticPrivateFieldSpecGet";
 
       return t.callExpression(file.addHelper(helperName), [
         this.receiver(member),
@@ -180,12 +181,14 @@ const privateNameHandlerSpec = {
       static: isStatic,
       method: isMethod,
       setId,
+      getId,
     } = privateNamesMap.get(name);
 
     if (isStatic) {
-      const helperName = isMethod
-        ? "classStaticPrivateMethodSet"
-        : "classStaticPrivateFieldSpecSet";
+      const helperName =
+        isMethod && !(getId || setId)
+          ? "classStaticPrivateMethodSet"
+          : "classStaticPrivateFieldSpecSet";
 
       return t.callExpression(file.addHelper(helperName), [
         this.receiver(member),
@@ -287,8 +290,47 @@ function buildPrivateInstanceFieldInitSpec(ref, prop, privateNamesMap) {
 }
 
 function buildPrivateStaticFieldInitSpec(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;
   const value = prop.node.value || prop.scope.buildUndefinedNode();
+  if (!prop.isProperty() && (initAdded || !(getId || setId))) return;
+
+  if (getId || setId) {
+    privateNamesMap.set(prop.node.key.id.name, {
+      ...privateName,
+      initAdded: true,
+    });
+
+    if (getId && setId) {
+      return template.statement.ast`
+        var ${id.name} = {
+          // 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`
+        var ${id.name} = {
+          // 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`
+        var ${id.name} = {
+          // configurable is false by default
+          // enumerable is false by default
+          // writable is false by default
+          set: ${setId.name}
+        }
+      `;
+    }
+  }
 
   return template.statement.ast`
     var ${id} = {
@@ -602,6 +644,9 @@ export function buildFieldsInitNodes(
       case isStatic && isPrivate && isMethod && !loose:
         needsClassRef = true;
         staticNodes.push(
+          buildPrivateStaticFieldInitSpec(prop, privateNamesMap),
+        );
+        staticNodes.unshift(
           buildPrivateMethodDeclaration(prop, privateNamesMap, loose),
         );
         break;
@@ -633,7 +678,7 @@ export function buildFieldsInitNodes(
   }
 
   return {
-    staticNodes,
+    staticNodes: staticNodes.filter(Boolean),
     instanceNodes: instanceNodes.filter(Boolean),
     wrapClass(path) {
       for (const prop of props) {

packages/babel-helpers/src/helpers.js

@@ -1128,6 +1128,9 @@ helpers.classStaticPrivateFieldSpecGet = helper("7.0.2")`
     if (receiver !== classConstructor) {
       throw new TypeError("Private static access of wrong provenance");
     }
+    if (descriptor.get) {
+      return descriptor.get.call(receiver);
+    }
     return descriptor.value;
   }
 `;
@@ -1137,13 +1140,18 @@ helpers.classStaticPrivateFieldSpecSet = helper("7.0.2")`
     if (receiver !== classConstructor) {
       throw new TypeError("Private static access of wrong provenance");
     }
-    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/private-static-method/this/output.js

@@ -16,12 +16,12 @@ class B extends A {
 
 }
 
-var _getA = function _getA() {
-  return babelHelpers.get(babelHelpers.getPrototypeOf(B), "a", this);
-};
-
 var _getB = function _getB() {
   return this.b;
 };
 
+var _getA = function _getA() {
+  return babelHelpers.get(babelHelpers.getPrototypeOf(B), "a", this);
+};
+
 var [getA, getB] = B.extract();

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

@@ -0,0 +1,23 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = "top secret string";
+
+  static get #privateStaticFieldValue() {
+    return Cl.#PRIVATE_STATIC_FIELD;
+  }
+
+  static set #privateStaticFieldValue(newValue) {
+    Cl.#PRIVATE_STATIC_FIELD = `Updated: ${newValue}`;
+  }
+
+  static getValue() {
+    return Cl.#privateStaticFieldValue;
+  }
+
+  static setValue() {
+    Cl.#privateStaticFieldValue = "dank";
+  }
+}
+
+expect(Cl.getValue()).toEqual("top secret string");
+Cl.setValue();
+expect(Cl.getValue()).toEqual("Updated: dank");

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

@@ -0,0 +1,19 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = "top secret string";
+
+  static get #privateStaticFieldValue() {
+    return Cl.#PRIVATE_STATIC_FIELD;
+  }
+
+  static set #privateStaticFieldValue(newValue) {
+    Cl.#PRIVATE_STATIC_FIELD = `Updated: ${newValue}`;
+  }
+
+  static getValue() {
+    return Cl.#privateStaticFieldValue;
+  }
+
+  static setValue() {
+    Cl.#privateStaticFieldValue = "dank";
+  }
+}

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

@@ -0,0 +1,27 @@
+class Cl {
+  static getValue() {
+    return babelHelpers.classStaticPrivateFieldSpecGet(Cl, Cl, _privateStaticFieldValue);
+  }
+
+  static setValue() {
+    babelHelpers.classStaticPrivateFieldSpecSet(Cl, Cl, _privateStaticFieldValue, "dank");
+  }
+
+}
+
+var _set_privateStaticFieldValue = function (newValue) {
+  babelHelpers.classStaticPrivateFieldSpecSet(Cl, Cl, _PRIVATE_STATIC_FIELD, `Updated: ${newValue}`);
+};
+
+var _get_privateStaticFieldValue = function () {
+  return babelHelpers.classStaticPrivateFieldSpecGet(Cl, Cl, _PRIVATE_STATIC_FIELD);
+};
+
+var _PRIVATE_STATIC_FIELD = {
+  writable: true,
+  value: "top secret string"
+};
+var _privateStaticFieldValue = {
+  get: _get_privateStaticFieldValue,
+  set: _set_privateStaticFieldValue
+};

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

@@ -0,0 +1,13 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = 0;
+
+  static set #privateStaticFieldValue(newValue) {
+    Cl.#PRIVATE_STATIC_FIELD = newValue;
+  }
+
+  static getPrivateStaticFieldValue() {
+    return Cl.#privateStaticFieldValue;
+  }
+}
+
+expect(Cl.getPrivateStaticFieldValue()).toBeUndefined();

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

@@ -0,0 +1,11 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = 0;
+
+  static set #privateStaticFieldValue(newValue) {
+    Cl.#PRIVATE_STATIC_FIELD = newValue;
+  }
+
+  static getPrivateStaticFieldValue() {
+    return Cl.#privateStaticFieldValue;
+  }
+}

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

@@ -0,0 +1,18 @@
+class Cl {
+  static getPrivateStaticFieldValue() {
+    return babelHelpers.classStaticPrivateFieldSpecGet(Cl, Cl, _privateStaticFieldValue);
+  }
+
+}
+
+var _set_privateStaticFieldValue = function (newValue) {
+  babelHelpers.classStaticPrivateFieldSpecSet(Cl, Cl, _PRIVATE_STATIC_FIELD, newValue);
+};
+
+var _PRIVATE_STATIC_FIELD = {
+  writable: true,
+  value: 0
+};
+var _privateStaticFieldValue = {
+  set: _set_privateStaticFieldValue
+};

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

@@ -0,0 +1,14 @@
+{
+  "plugins": [
+    [
+      "external-helpers",
+      {
+        "helperVersion": "7.1000.0"
+      }
+    ],
+    "proposal-private-methods",
+    "proposal-class-properties",
+    "transform-block-scoping",
+    "syntax-class-properties"
+  ]
+}

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

@@ -0,0 +1,13 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = 0;
+
+  static get #privateStaticFieldValue() {
+    return Cl.#PRIVATE_STATIC_FIELD;
+  }
+
+  static setPrivateStaticFieldValue() {
+    Cl.#privateStaticFieldValue = 1;
+  }
+}
+
+expect(() => Cl.setPrivateStaticFieldValue()).toThrow(TypeError);

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

@@ -0,0 +1,11 @@
+class Cl {
+  static #PRIVATE_STATIC_FIELD = 0;
+
+  static get #privateStaticFieldValue() {
+    return Cl.#PRIVATE_STATIC_FIELD;
+  }
+
+  static setPrivateStaticFieldValue() {
+    Cl.#privateStaticFieldValue = 1;
+  }
+}

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

@@ -0,0 +1,18 @@
+class Cl {
+  static setPrivateStaticFieldValue() {
+    babelHelpers.classStaticPrivateFieldSpecSet(Cl, Cl, _privateStaticFieldValue, 1);
+  }
+
+}
+
+var _get_privateStaticFieldValue = function () {
+  return babelHelpers.classStaticPrivateFieldSpecGet(Cl, Cl, _PRIVATE_STATIC_FIELD);
+};
+
+var _PRIVATE_STATIC_FIELD = {
+  writable: true,
+  value: 0
+};
+var _privateStaticFieldValue = {
+  get: _get_privateStaticFieldValue
+};

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

@@ -0,0 +1,46 @@
+class Cl {
+  static #privateField = "top secret string";
+  static publicField = "not secret string";
+
+  static get #privateFieldValue() {
+    return Cl.#privateField;
+  }
+
+  static set #privateFieldValue(newValue) {
+    Cl.#privateField = newValue;
+  }
+
+  static publicGetPrivateField() {
+    return Cl.#privateFieldValue;
+  }
+
+  static publicSetPrivateField(newValue) {
+    Cl.#privateFieldValue = newValue;
+  }
+
+  static get publicFieldValue() {
+    return Cl.publicField;
+  }
+
+  static set publicFieldValue(newValue) {
+    Cl.publicField = newValue;
+  }
+
+  static testUpdates() {
+    Cl.#privateField = 0;
+    Cl.publicField = 0;
+    Cl.#privateFieldValue = Cl.#privateFieldValue++;
+    Cl.publicFieldValue = Cl.publicFieldValue++;
+    expect(Cl.#privateField).toEqual(Cl.publicField);
+
+    ++Cl.#privateFieldValue;
+    ++Cl.publicFieldValue;
+    expect(Cl.#privateField).toEqual(Cl.publicField);
+
+    Cl.#privateFieldValue += 1;
+    Cl.publicFieldValue += 1;
+    expect(Cl.#privateField).toEqual(Cl.publicField);
+  }
+}
+
+Cl.testUpdates();