Support multiple static blocks (#12738)

packages/babel-parser/src/parser/error-message.js

@@ -49,7 +49,6 @@ export const ErrorMessages = Object.freeze({
     "`%0` has already been exported. Exported identifiers must be unique.",
   DuplicateProto: "Redefinition of __proto__ property",
   DuplicateRegExpFlags: "Duplicate regular expression flag",
-  DuplicateStaticBlock: "Duplicate static block in the same class",
   ElementAfterRest: "Rest element must be last element",
   EscapedCharNotAnIdentifier: "Invalid Unicode escape",
   ExportBindingIsString:

packages/babel-parser/src/parser/statement.js

@@ -1204,7 +1204,6 @@ export default class StatementParser extends ExpressionParser {
     const state: N.ParseClassMemberState = {
       constructorAllowsSuper,
       hadConstructor: false,
-      hadStaticBlock: false,
     };
     let decorators: N.Decorator[] = [];
     const classBody: N.ClassBody = this.startNode();
@@ -1313,11 +1312,7 @@ export default class StatementParser extends ExpressionParser {
         return;
       }
       if (this.eat(tt.braceL)) {
-        this.parseClassStaticBlock(
-          classBody,
-          ((member: any): N.StaticBlock),
-          state,
-        );
+        this.parseClassStaticBlock(classBody, ((member: any): N.StaticBlock));
         return;
       }
     }
@@ -1521,7 +1516,6 @@ export default class StatementParser extends ExpressionParser {
   parseClassStaticBlock(
     classBody: N.ClassBody,
     member: N.StaticBlock & { decorators?: Array<N.Decorator> },
-    state: N.ParseClassMemberState,
   ) {
     this.expectPlugin("classStaticBlock", member.start);
     // Start a new lexical scope
@@ -1538,13 +1532,9 @@ export default class StatementParser extends ExpressionParser {
     this.scope.exit();
     this.state.labels = oldLabels;
     classBody.body.push(this.finishNode<N.StaticBlock>(member, "StaticBlock"));
-    if (state.hadStaticBlock) {
-      this.raise(member.start, Errors.DuplicateStaticBlock);
-    }
     if (member.decorators?.length) {
       this.raise(member.start, Errors.DecoratorStaticBlock);
     }
-    state.hadStaticBlock = true;
   }
 
   pushClassProperty(classBody: N.ClassBody, prop: N.ClassProperty) {

packages/babel-parser/src/types.js

@@ -1528,6 +1528,5 @@ export type ParseSubscriptState = {
 
 export type ParseClassMemberState = {|
   hadConstructor: boolean,
-  hadStaticBlock: boolean,
   constructorAllowsSuper: boolean,
 |};

packages/babel-parser/test/fixtures/experimental/class-static-block/invalid-duplicated-static-block/output.json → packages/babel-parser/test/fixtures/experimental/class-static-block/multiple-static-block/output.json

@@ -1,9 +1,6 @@
 {
   "type": "File",
   "start":0,"end":53,"loc":{"start":{"line":1,"column":0},"end":{"line":5,"column":1}},
-  "errors": [
-    "SyntaxError: Duplicate static block in the same class (4:2)"
-  ],
   "program": {
     "type": "Program",
     "start":0,"end":53,"loc":{"start":{"line":1,"column":0},"end":{"line":5,"column":1}},

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

@@ -30,30 +30,28 @@ export default declare(({ types: t, template, assertVersion }) => {
         const { scope } = path;
         const classBody = path.get("body");
         const privateNames = new Set();
-        let staticBlockPath;
-        for (const path of classBody.get("body")) {
+        const body = classBody.get("body");
+        for (const path of body) {
           if (path.isPrivate()) {
             privateNames.add(path.get("key.id").node.name);
-          } else if (path.isStaticBlock()) {
-            staticBlockPath = path;
           }
         }
-        if (!staticBlockPath) {
-          return;
+        for (const path of body) {
+          if (!path.isStaticBlock()) continue;
+          const staticBlockPrivateId = generateUid(scope, privateNames);
+          privateNames.add(staticBlockPrivateId);
+          const staticBlockRef = t.privateName(
+            t.identifier(staticBlockPrivateId),
+          );
+          path.replaceWith(
+            t.classPrivateProperty(
+              staticBlockRef,
+              template.expression.ast`(() => { ${path.node.body} })()`,
+              [],
+              /* static */ true,
+            ),
+          );
         }
-        const staticBlockRef = t.privateName(
-          t.identifier(generateUid(scope, privateNames)),
-        );
-        classBody.pushContainer(
-          "body",
-          t.classPrivateProperty(
-            staticBlockRef,
-            template.expression.ast`(() => { ${staticBlockPath.node.body} })()`,
-            [],
-            /* static */ true,
-          ),
-        );
-        staticBlockPath.remove();
       },
     },
   };

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

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

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

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

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

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

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

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

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

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

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

@@ -1,8 +1,14 @@
 class Foo {
   static #bar = 21;
   static {
-    this.foo = this.#bar + this.qux;
+    this.foo = this.#bar;
+    this.qux1 = this.qux;
   }
   static qux = 21;
+  static {
+    this.qux2 = this.qux;
+  }
 }
-expect(Foo.foo).toBe(42);
+expect(Foo.foo).toBe(21);
+expect(Foo.qux1).toBe(undefined);
+expect(Foo.qux2).toBe(21);

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

@@ -0,0 +1,11 @@
+class Foo {
+  static #bar = 21;
+  static {
+    this.foo = this.#bar;
+    this.qux1 = this.qux;
+  }
+  static qux = 21;
+  static {
+    this.qux2 = this.qux;
+  }
+}

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

@@ -0,0 +1,11 @@
+class Foo {
+  static #bar = 21;
+  static #_ = (() => {
+    this.foo = this.#bar;
+    this.qux1 = this.qux;
+  })();
+  static qux = 21;
+  static #_2 = (() => {
+    this.qux2 = this.qux;
+  })();
+}

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

@@ -0,0 +1,10 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/class-static-block/new-target/input.js

@@ -0,0 +1,10 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/class-static-block/new-target/output.js

@@ -0,0 +1,12 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static #_ = (() => {
+        this.foo = new.target;
+      })();
+    };
+  }
+
+}
+
+expect(new Base().Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration-loose/.new-target/exec.js

@@ -0,0 +1,10 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

packages/babel-plugin-proposal-class-static-block/test/fixtures/integration-loose/.new-target/input.js

@@ -0,0 +1,10 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

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

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

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

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

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

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

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

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

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

@@ -1,8 +1,14 @@
 class Foo {
   static #bar = 21;
   static {
-    this.foo = this.#bar + this.qux;
+    this.foo = this.#bar;
+    this.qux1 = this.qux;
   }
   static qux = 21;
+  static {
+    this.qux2 = this.qux;
+  }
 }
-expect(Foo.foo).toBe(42);
+expect(Foo.foo).toBe(21);
+expect(Foo.qux1).toBe(undefined);
+expect(Foo.qux2).toBe(21);

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

@@ -0,0 +1,11 @@
+class Foo {
+  static #bar = 21;
+  static {
+    this.foo = this.#bar;
+    this.qux1 = this.qux;
+  }
+  static qux = 21;
+  static {
+    this.qux2 = this.qux;
+  }
+}

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

@@ -0,0 +1,26 @@
+var _bar = babelHelpers.classPrivateFieldLooseKey("bar");
+
+var _ = babelHelpers.classPrivateFieldLooseKey("_");
+
+var _2 = babelHelpers.classPrivateFieldLooseKey("_2");
+
+class Foo {}
+
+Object.defineProperty(Foo, _bar, {
+  writable: true,
+  value: 21
+});
+Object.defineProperty(Foo, _, {
+  writable: true,
+  value: (() => {
+    Foo.foo = babelHelpers.classPrivateFieldLooseBase(Foo, _bar)[_bar];
+    Foo.qux1 = Foo.qux;
+  })()
+});
+Foo.qux = 21;
+Object.defineProperty(Foo, _2, {
+  writable: true,
+  value: (() => {
+    Foo.qux2 = Foo.qux;
+  })()
+});

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

@@ -0,0 +1,10 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

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

@@ -0,0 +1,11 @@
+class Base {
+  constructor() {
+    this.Foo = class {
+      static {
+        // fixme: new.target should be undefined after transformed
+        this.foo = new.target;
+      }
+    }
+  }
+}
+expect((new Base).Foo.foo).toBe(undefined);

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

@@ -1,7 +1,7 @@
 class Foo {
+  static bar = 42;
   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

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

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

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