From b3f2ea0aa1075df1a5782d5444e922c2c95167d2 Mon Sep 17 00:00:00 2001
From: Logan Smyth <loganfsmyth@gmail.com>
Date: Wed, 18 Nov 2015 23:57:01 -0800
Subject: [PATCH] Avoid duplicating traversal of class declarations - fixes
 T2694

---
 .../general/static-export/expected.js         |  2 +-
 .../src/index.js                              | 17 ++++---
 .../test/fixtures/regression/3028/actual.js   | 16 +++++++
 .../test/fixtures/regression/3028/expected.js | 45 +++++++++++++++++++
 4 files changed, 74 insertions(+), 6 deletions(-)
 create mode 100644 packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/actual.js
 create mode 100644 packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/expected.js

diff --git a/packages/babel-plugin-transform-class-properties/test/fixtures/general/static-export/expected.js b/packages/babel-plugin-transform-class-properties/test/fixtures/general/static-export/expected.js
index 0405f67721..848dfbe5f6 100644
--- a/packages/babel-plugin-transform-class-properties/test/fixtures/general/static-export/expected.js
+++ b/packages/babel-plugin-transform-class-properties/test/fixtures/general/static-export/expected.js
@@ -8,5 +8,5 @@ var MyClass2 = function MyClass2() {
   babelHelpers.classCallCheck(this, MyClass2);
 };
 
-export default MyClass2;
 MyClass2.property = value;
+export default MyClass2;
diff --git a/packages/babel-plugin-transform-es2015-classes/src/index.js b/packages/babel-plugin-transform-es2015-classes/src/index.js
index bc7dff95eb..f922f99437 100644
--- a/packages/babel-plugin-transform-es2015-classes/src/index.js
+++ b/packages/babel-plugin-transform-es2015-classes/src/index.js
@@ -8,16 +8,23 @@ export default function ({ types: t }) {
 
   return {
     visitor: {
+      ExportDefaultDeclaration(path){
+        if (!path.get("declaration").isClassDeclaration()) return;
+
+        let { node } = path;
+        let ref = node.declaration.id || path.scope.generateUidIdentifier("class");
+        node.declaration.id = ref;
+
+        // Split the class declaration and the export into two separate statements.
+        path.replaceWith(node.declaration);
+        path.insertAfter(t.exportDefaultDeclaration(ref));
+      },
+
       ClassDeclaration(path) {
         let { node } = path;
 
         let ref = node.id || path.scope.generateUidIdentifier("class");
 
-        if (path.parentPath.isExportDefaultDeclaration()) {
-          path = path.parentPath;
-          path.insertAfter(t.exportDefaultDeclaration(ref));
-        }
-
         path.replaceWith(t.variableDeclaration("let", [
           t.variableDeclarator(ref, t.toExpression(node))
         ]));
diff --git a/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/actual.js b/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/actual.js
new file mode 100644
index 0000000000..2917b57938
--- /dev/null
+++ b/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/actual.js
@@ -0,0 +1,16 @@
+class b {
+}
+
+class a1 extends b {
+  constructor() {
+    super();
+    this.x = () => this;
+  }
+}
+
+export default class a2 extends b {
+  constructor() {
+    super();
+    this.x = () => this;
+  }
+}
diff --git a/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/expected.js b/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/expected.js
new file mode 100644
index 0000000000..8828aee19c
--- /dev/null
+++ b/packages/babel-plugin-transform-es2015-classes/test/fixtures/regression/3028/expected.js
@@ -0,0 +1,45 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+
+var b = function b() {
+  babelHelpers.classCallCheck(this, b);
+};
+
+var a1 = (function (_b) {
+  babelHelpers.inherits(a1, _b);
+
+  function a1() {
+    babelHelpers.classCallCheck(this, a1);
+
+    var _this = babelHelpers.possibleConstructorReturn(this, Object.getPrototypeOf(a1).call(this));
+
+    _this.x = function () {
+      return _this;
+    };
+    return _this;
+  }
+
+  return a1;
+})(b);
+
+var a2 = (function (_b2) {
+  babelHelpers.inherits(a2, _b2);
+
+  function a2() {
+    babelHelpers.classCallCheck(this, a2);
+
+    var _this2 = babelHelpers.possibleConstructorReturn(this, Object.getPrototypeOf(a2).call(this));
+
+    _this2.x = function () {
+      return _this2;
+    };
+    return _this2;
+  }
+
+  return a2;
+})(b);
+
+exports.default = a2;