refactor: tap in Class visitor to play nicely with class transforms

packages/babel-plugin-proposal-class-static-block/src/index.js

@@ -19,22 +19,6 @@ function generateUid(scope, denyList: Set<string>) {
   return uid;
 }
 
-/**
- * Get private names defined in current class body
- *
- * @param {NodePath<ClassBody>} classBody
- * @returns {Set<string>} A set of defined private names
- */
-function getPrivateNames(classBody: NodePath<ClassBody>): Set<string> {
-  const privateNames = new Set();
-  for (const path of classBody.get("body")) {
-    if (path.isPrivate()) {
-      privateNames.add(path.get("key.id").node.name);
-    }
-  }
-  return privateNames;
-}
-
 export default declare(({ types: t, template, assertVersion }) => {
   // todo remove this check after Babel 7.12.0 is published
   if (process.env.NODE_ENV !== "test") {
@@ -45,21 +29,35 @@ export default declare(({ types: t, template, assertVersion }) => {
     name: "proposal-class-static-block",
     inherits: syntaxClassStaticBlock,
     visitor: {
-      StaticBlock(path: NodePath<StaticBlock>) {
-        const { parentPath: classBody, scope } = path;
+      Class(path: NodePath<Class>) {
+        const { scope } = path;
+        const classBody = path.get("body");
+        const privateNames = new Set();
+        let staticBlockPath;
+        for (const path of classBody.get("body")) {
+          if (path.isPrivate()) {
+            privateNames.add(path.get("key.id").node.name);
+          } else if (path.isStaticBlock()) {
+            staticBlockPath = path;
+          }
+        }
+        if (!staticBlockPath) {
+          return;
+        }
         const staticBlockRef = t.privateName(
-          t.identifier(generateUid(scope, getPrivateNames(classBody))),
+          t.identifier(generateUid(scope, privateNames)),
         );
         classBody.pushContainer(
           "body",
           t.classPrivateProperty(
             staticBlockRef,
-            template.expression.ast`(() => { ${path.node.body} })()`,
+            template.expression.ast`(() => { ${staticBlockPath.node.body} })()`,
             [],
             /* static */ true,
           ),
         );
-        path.remove();
+        staticBlockPath.remove();
+        path.requeue();
       },
     },
   };

packages/babel-plugin-proposal-class-static-block/test/fixtures/class-static-block/non-static/exec.js

@@ -0,0 +1,7 @@
+class Foo {
+  bar = 21;
+  static {
+    this.foo = this.bar;
+  }
+}
+expect(Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-binding/exec.js

@@ -0,0 +1,7 @@
+class Foo {
+  static {
+    this.foo = Foo.bar;
+  }
+  static bar = 42;
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-binding/input.js

@@ -0,0 +1,7 @@
+class Foo {
+  static {
+    this.foo = Foo.bar;
+  }
+  static bar = 42;
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-binding/output.js

@@ -0,0 +1,10 @@
+class Foo {}
+
+babelHelpers.defineProperty(Foo, "bar", 42);
+var _ = {
+  writable: true,
+  value: (() => {
+    Foo.foo = Foo.bar;
+  })()
+};
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-declaration/exec.js

@@ -0,0 +1,7 @@
+class Foo {
+  static {
+    this.foo = this.bar;
+  }
+  static bar = 42;
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-declaration/input.js

@@ -0,0 +1,7 @@
+class Foo {
+  static {
+    this.foo = this.bar;
+  }
+  static bar = 42;
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-declaration/output.js

@@ -0,0 +1,10 @@
+class Foo {}
+
+babelHelpers.defineProperty(Foo, "bar", 42);
+var _ = {
+  writable: true,
+  value: (() => {
+    Foo.foo = Foo.bar;
+  })()
+};
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/class-expression/exec.js

@@ -0,0 +1,6 @@
+class Foo {
+  static {
+    this.foo = 42;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/in-class-heritage/exec.js

@@ -0,0 +1,14 @@
+class Foo extends class extends class Base {
+  static {
+    this.qux = 21;
+  }
+} {
+  static {
+    this.bar = 21;
+  }
+} {
+  static {
+    this.foo = this.bar + this.qux;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/in-class-heritage/input.js

@@ -0,0 +1,14 @@
+class Foo extends class extends class Base {
+  static {
+    this.qux = 21;
+  }
+} {
+  static {
+    this.bar = 21;
+  }
+} {
+  static {
+    this.foo = this.bar + this.qux;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/in-class-heritage/output.js

@@ -0,0 +1,21 @@
+var _class, _temp, _2, _class2, _temp2, _3;
+
+class Foo extends (_temp = _class = class extends (_temp2 = _class2 = class Base {}, _3 = {
+  writable: true,
+  value: (() => {
+    _class2.qux = 21;
+  })()
+}, _temp2) {}, _2 = {
+  writable: true,
+  value: (() => {
+    _class.bar = 21;
+  })()
+}, _temp) {}
+
+var _ = {
+  writable: true,
+  value: (() => {
+    Foo.foo = Foo.bar + Foo.qux;
+  })()
+};
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/multiple-static-initializers/exec.js

@@ -0,0 +1,8 @@
+class Foo {
+  static #bar = 21;
+  static {
+    this.foo = this.#bar + this.qux;
+  }
+  static qux = 21;
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/name-conflict/exec.js

@@ -0,0 +1,8 @@
+class Foo {
+  static #_ = 42;
+  // static block can not be tranformed as `#_` here
+  static {
+    this.foo = this.#_;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/name-conflict/input.js

@@ -0,0 +1,8 @@
+class Foo {
+  static #_ = 42;
+  // static block can not be tranformed as `#_` here
+  static {
+    this.foo = this.#_;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/name-conflict/output.js

@@ -0,0 +1,15 @@
+function _classStaticPrivateFieldSpecGet(receiver, classConstructor, descriptor) { if (receiver !== classConstructor) { throw new TypeError("Private static access of wrong provenance"); } if (descriptor.get) { return descriptor.get.call(receiver); } return descriptor.value; }
+
+class Foo {}
+
+var _ = {
+  writable: true,
+  value: 42
+};
+var _2 = {
+  writable: true,
+  value: (() => {
+    Foo.foo = _classStaticPrivateFieldSpecGet(Foo, Foo, _);
+  })()
+};
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/non-static/exec.js

@@ -0,0 +1,7 @@
+class Foo {
+  bar = 21;
+  static {
+    this.foo = this.bar;
+  }
+}
+expect(Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/options.json

@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    "proposal-class-static-block",
+    "proposal-class-properties",
+    "external-helpers"
+  ]
+}

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/private-elements-access/exec.js

@@ -0,0 +1,8 @@
+let getFoo;
+class Foo {
+  static #foo = 42;
+  static {
+    getFoo = () => this.#foo;
+  }
+}
+expect(getFoo()).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration/super-property/exec.js

@@ -0,0 +1,11 @@
+class Foo extends class {
+  static {
+    this.bar = 42;
+  }
+} {
+  static bar = 21;
+  static {
+    this.foo = super.bar;
+  }
+}
+expect(Foo.foo).toBe(42);

packages/babel-plugin-proposal-class-static-block/test/plugin-ordering.test.js

@@ -0,0 +1,42 @@
+import * as babel from "@babel/core";
+import proposalClassStaticBlock from "../lib/index.js";
+
+describe("plugin ordering", () => {
+  it("should throw when @babel/plugin-proposal-class-static-block is after class features plugin", () => {
+    const source = `class Foo {
+  static {
+    this.foo = Foo.bar;
+  }
+  static bar = 42;
+}
+`;
+    expect(() => {
+      babel.transform(source, {
+        filename: "example.js",
+        highlightCode: false,
+        configFile: false,
+        babelrc: false,
+        plugins: [
+          "@babel/plugin-proposal-class-properties",
+          proposalClassStaticBlock,
+        ],
+      });
+    }).toThrowErrorMatchingInlineSnapshot(`
+"/Users/jh/code/babel/example.js: Incorrect plugin orders, \`@babel/plugin-proposal-class-static-block\` should be placed before class features plugins
+{
+  \\"plugins\\": [
+    \\"@babel/plugin-proposal-class-static-block\\",
+    \\"@babel/plugin-proposal-private-property-in-object\\",
+    \\"@babel/plugin-proposal-private-methods\\",
+    \\"@babel/plugin-proposal-class-properties\\",
+  ]
+}
+  1 | class Foo {
+> 2 |   static {
+    |   ^
+  3 |     this.foo = Foo.bar;
+  4 |   }
+  5 |   static bar = 42;"
+`);
+  });
+});