fix

liuxingbaoyu · liuxingbaoyu · commit 26e4d3a51c0d · 2025-12-28T09:03:10.000+08:00
diff --git a/packages/babel-plugin-transform-block-scoped-functions/src/index.ts b/packages/babel-plugin-transform-block-scoped-functions/src/index.ts
@@ -8,27 +8,21 @@ export default declare(api => {
     parentPath: NodePath,
     paths: NodePath<t.Statement>[],
   ) {
-    // eslint-disable-next-line no-var
-    var isInStrictMode = parentPath.isInStrictMode();
+    const isInStrictMode = parentPath.isInStrictMode();
 
     for (const path of paths) {
       if (!path.isFunctionDeclaration()) continue;
 
-      if (
-        !isInStrictMode &&
-        !(
-          path.node.async ||
-          path.node.generator ||
-          path.getData(
-            "@babel/plugin-transform-async-generator-functions/async_generator_function",
-          )
-        )
-      ) {
-        continue;
-      }
+      const useLet =
+        isInStrictMode ||
+        path.node.async ||
+        path.node.generator ||
+        path.getData(
+          "@babel/plugin-transform-async-generator-functions/async_generator_function",
+        );
 
       const func = path.node;
-      const declar = t.variableDeclaration("let", [
+      const declar = t.variableDeclaration(useLet ? "let" : "var", [
         t.variableDeclarator(func.id, t.toExpression(func)),
       ]);
 
diff --git a/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/input.js b/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/input.js
@@ -0,0 +1,54 @@
+function strictMode() {
+  "use strict";
+
+  // https://github.com/compat-table/compat-table/blob/f12538fe11c48c4fd35d6cdc7789653e10871b90/data-es6.js#L14429-L14446
+
+  console.assert(a() === 1);
+  function a() {
+    return 1;
+  }
+  console.assert(a() === 1);
+  {
+    console.assert(a() === 2);
+    function a() {
+      return 2;
+    }
+    console.assert(a() === 2);
+  }
+  console.assert(a() === 1);
+}
+function nonStrictMode() {
+  // https://github.com/compat-table/compat-table/blob/f12538fe11c48c4fd35d6cdc7789653e10871b90/data-es6.js#L4269-L4286
+
+  console.assert(typeof a === "undefined");
+  {
+    function a() {
+      return 1;
+    }
+  }
+  console.assert(a() === 1);
+
+  console.assert(b() === 2);
+  {
+    function b() {
+      return 1;
+    }
+  }
+  function b() {
+    return 2;
+  }
+  console.assert(b() === 1);
+
+  function c() {
+    return 1;
+  }
+  switch (0) {
+    case 1:
+      function c() {
+        return 2;
+      }
+  }
+  console.assert(c() === 1);
+}
+strictMode();
+nonStrictMode();
diff --git a/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/options.json b/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/options.json
@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    "transform-block-scoped-functions",
+    "transform-block-scoping"
+  ]
+}
diff --git a/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/output.js b/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/node-v0.10/output.js
@@ -0,0 +1,51 @@
+function strictMode() {
+  "use strict";
+
+  // https://github.com/compat-table/compat-table/blob/f12538fe11c48c4fd35d6cdc7789653e10871b90/data-es6.js#L14429-L14446
+  console.assert(a() === 1);
+  function a() {
+    return 1;
+  }
+  console.assert(a() === 1);
+  {
+    var _a = function () {
+      return 2;
+    };
+    console.assert(_a() === 2);
+    console.assert(_a() === 2);
+  }
+  console.assert(a() === 1);
+}
+function nonStrictMode() {
+  // https://github.com/compat-table/compat-table/blob/f12538fe11c48c4fd35d6cdc7789653e10871b90/data-es6.js#L4269-L4286
+
+  console.assert(typeof a === "undefined");
+  {
+    var a = function () {
+      return 1;
+    };
+  }
+  console.assert(a() === 1);
+  console.assert(b() === 2);
+  {
+    var b = function () {
+      return 1;
+    };
+  }
+  function b() {
+    return 2;
+  }
+  console.assert(b() === 1);
+  function c() {
+    return 1;
+  }
+  switch (0) {
+    case 1:
+      var c = function () {
+        return 2;
+      };
+  }
+  console.assert(c() === 1);
+}
+strictMode();
+nonStrictMode();
diff --git a/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/scope-lex-async-generator/output.js b/packages/babel-plugin-transform-block-scoped-functions/test/fixtures/block-scoped-functions/scope-lex-async-generator/output.js
@@ -25,10 +25,10 @@ expect(() => {
       var _x2 = function () {
         return _x.apply(this, arguments);
       };
-      function _x() {
+      var _x = function () {
         _x = babelHelpers.wrapAsyncGenerator(function* () {});
         return _x.apply(this, arguments);
-      }
+      };
   }
   x;
 }).toThrow(ReferenceError);
diff --git a/packages/babel-plugin-transform-block-scoping/src/annex-B_3_3.ts b/packages/babel-plugin-transform-block-scoping/src/annex-B_3_3.ts
diff --git a/packages/babel-plugin-transform-block-scoping/src/index.ts b/packages/babel-plugin-transform-block-scoping/src/index.ts
@@ -9,7 +9,6 @@ import {
   wrapLoopBody,
 } from "./loop.ts";
 import { validateUsage } from "./validation.ts";
-import { annexB33FunctionsVisitor, isVarScope } from "./annex-B_3_3.ts";
 
 export interface Options {
   tdz?: boolean;
@@ -31,8 +30,6 @@ export default declare((api, opts: Options) => {
     name: "transform-block-scoping",
 
     visitor: traverse.visitors.merge<PluginPass>([
-      // TODO: Consider adding an option to control Annex B behavior.
-      annexB33FunctionsVisitor,
       {
         Loop(path: NodePath<t.Loop>, state) {
           const isForStatement = path.isForStatement();
@@ -272,3 +269,7 @@ function isBlockScoped(
 
   return true;
 }
+
+export function isVarScope(scope: Scope) {
+  return scope.path.isFunctionParent() || scope.path.isProgram();
+}
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3-collision-const/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3-collision-const/output.js
@@ -2,9 +2,9 @@ var run = function () {
   return false;
 };
 if (true) {
-  function _run() {
+  var _run = function () {
     return true;
-  }
+  };
 }
 function test() {
   return run();
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3-collision-let/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3-collision-let/output.js
@@ -2,9 +2,9 @@ var run = function () {
   return false;
 };
 if (true) {
-  function _run() {
+  var _run = function () {
     return true;
-  }
+  };
 }
 function test() {
   return run();
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/annex-B_3_3/output.js
@@ -1,7 +1,7 @@
 if (true) {
-  function run() {
+  var run = function () {
     return true;
-  }
+  };
 }
 function test() {
   return run();
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/function-in-catch/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/function-in-catch/output.js
@@ -1,7 +1,7 @@
 try {
   foo();
 } catch (x) {
-  function harmless(x) {
+  var harmless = function (x) {
     return x;
-  }
+  };
 }
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-1051/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-1051/output.js
@@ -2,8 +2,8 @@ foo.func1 = function () {
   if (cond1) {
     var _loop = function () {
       if (cond2) {
-        function func2() {}
-        function func3() {}
+        var func2 = function () {};
+        var func3 = function () {};
         func4(function () {
           func2();
         });
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-14960/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-14960/output.js
@@ -1,9 +1,9 @@
 {
   switch (1) {
     case 1:
-      expect(f()).toBe(1);
-      function f() {
+      var f = function () {
         return 1;
-      }
+      };
+      expect(f()).toBe(1);
   }
 }
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-2174/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/issue-2174/output.js
@@ -1,7 +1,7 @@
 if (true) {
-  function foo() {}
-  function bar() {
+  var foo = function () {};
+  var bar = function () {
     return foo;
-  }
+  };
   for (var x in {}) {}
 }
diff --git a/packages/babel-plugin-transform-block-scoping/test/fixtures/general/switch/output.js b/packages/babel-plugin-transform-block-scoping/test/fixtures/general/switch/output.js
@@ -19,6 +19,6 @@ switch (true) {
     var _c = 4;
     var _d = 5;
   case false:
+    var f = function () {};
     class _e {}
-    function f() {}
 }
diff --git a/packages/babel-preset-env/test/fixtures/plugins-integration/block-scoping-block-scoped-function/output.js b/packages/babel-preset-env/test/fixtures/plugins-integration/block-scoping-block-scoped-function/output.js
@@ -1,6 +1,6 @@
 if (true) {
-  function run() {
+  var run = function run() {
     return true;
-  }
+  };
 }
 expect(run()).toBe(true);
