From 0f7da020e35af12a26b53e1f395dbbdc3ec4fbb4 Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Sun, 12 Oct 2014 00:23:13 +1100
Subject: [PATCH] change obj references to a unique identifier

---
 lib/6to5/templates/function-return-obj-this.js            | 4 ++--
 lib/6to5/templates/function-return-obj.js                 | 4 ++--
 lib/6to5/templates/obj-key-set.js                         | 2 +-
 lib/6to5/templates/object-define-properties-closure.js    | 4 ++--
 lib/6to5/transformers/computed-property-names.js          | 7 ++++++-
 lib/6to5/transformers/for-of.js                           | 2 +-
 lib/6to5/transformers/property-method-assignment.js       | 7 +++++--
 lib/6to5/traverse/index.js                                | 4 +++-
 .../syntax/computed-property-names/method/expected.js     | 6 +++---
 .../syntax/computed-property-names/mixed/expected.js      | 8 ++++----
 .../syntax/computed-property-names/multiple/expected.js   | 8 ++++----
 .../syntax/computed-property-names/single/expected.js     | 6 +++---
 .../syntax/computed-property-names/this/expected.js       | 6 +++---
 .../getter-and-setter/expected.js                         | 6 +++---
 .../syntax/property-methods-assignment/getter/expected.js | 6 +++---
 .../syntax/property-methods-assignment/setter/expected.js | 6 +++---
 16 files changed, 48 insertions(+), 38 deletions(-)

diff --git a/lib/6to5/templates/function-return-obj-this.js b/lib/6to5/templates/function-return-obj-this.js
index 0a69bc5022..99b9dd6df4 100644
--- a/lib/6to5/templates/function-return-obj-this.js
+++ b/lib/6to5/templates/function-return-obj-this.js
@@ -1,3 +1,3 @@
-(function (obj) {
-  return obj;
+(function (KEY) {
+  return KEY;
 }).call(this, OBJECT)
diff --git a/lib/6to5/templates/function-return-obj.js b/lib/6to5/templates/function-return-obj.js
index 2ccd4cd89c..4f54b679b9 100644
--- a/lib/6to5/templates/function-return-obj.js
+++ b/lib/6to5/templates/function-return-obj.js
@@ -1,3 +1,3 @@
-(function (obj) {
-  return obj;
+(function (KEY) {
+  return KEY;
 })(OBJECT)
diff --git a/lib/6to5/templates/obj-key-set.js b/lib/6to5/templates/obj-key-set.js
index 3f37b446d3..6663140995 100644
--- a/lib/6to5/templates/obj-key-set.js
+++ b/lib/6to5/templates/obj-key-set.js
@@ -1 +1 @@
-obj[KEY] = VALUE;
+OBJECT_KEY[KEY] = VALUE;
diff --git a/lib/6to5/templates/object-define-properties-closure.js b/lib/6to5/templates/object-define-properties-closure.js
index c09c638d3f..a7b90fbc8c 100644
--- a/lib/6to5/templates/object-define-properties-closure.js
+++ b/lib/6to5/templates/object-define-properties-closure.js
@@ -1,4 +1,4 @@
-(function (obj) {
+(function (KEY) {
   CONTENT;
-  return obj;
+  return KEY;
 })(OBJECT);
diff --git a/lib/6to5/transformers/computed-property-names.js b/lib/6to5/transformers/computed-property-names.js
index 7d931f35b6..00dd77cbeb 100644
--- a/lib/6to5/transformers/computed-property-names.js
+++ b/lib/6to5/transformers/computed-property-names.js
@@ -1,8 +1,9 @@
 var traverse = require("../traverse");
 var util     = require("../util");
+var b        = require("ast-types").builders;
 var _        = require("lodash");
 
-exports.ObjectExpression = function (node) {
+exports.ObjectExpression = function (node, parent, opts, generateUid) {
   var hasComputed = false;
   var hasThis     = false;
 
@@ -24,7 +25,10 @@ exports.ObjectExpression = function (node) {
   var templateName = "function-return-obj";
   if (hasThis) templateName += "-this";
 
+  var objId = b.identifier(generateUid("ref"));
+
   var container = util.template(templateName, {
+    KEY: objId,
     OBJECT: node
   });
 
@@ -37,6 +41,7 @@ exports.ObjectExpression = function (node) {
 
   _.each(computed, function (prop) {
     containerBody.unshift(util.template("obj-key-set", {
+      OBJECT_KEY: objId,
       KEY: prop.key,
       VALUE: prop.value
     }, true));
diff --git a/lib/6to5/transformers/for-of.js b/lib/6to5/transformers/for-of.js
index 30f4fd8d97..26f71b0700 100644
--- a/lib/6to5/transformers/for-of.js
+++ b/lib/6to5/transformers/for-of.js
@@ -22,7 +22,7 @@ exports.ForOfStatement = function (node, parent, opts, generateUid) {
   util.ensureBlock(node);
 
   var block = node2.body;
-  block.body = block.body.concat(node.body.body || []);
+  block.body = block.body.concat(node.body.body);
 
   var declar  = block.body[0];
   declar.kind = declar.kind;
diff --git a/lib/6to5/transformers/property-method-assignment.js b/lib/6to5/transformers/property-method-assignment.js
index 8ed7f130f2..a37e2f9f54 100644
--- a/lib/6to5/transformers/property-method-assignment.js
+++ b/lib/6to5/transformers/property-method-assignment.js
@@ -6,7 +6,7 @@ exports.Property = function (node) {
   if (node.method) node.method = false;
 };
 
-exports.ObjectExpression = function (node) {
+exports.ObjectExpression = function (node, parent, opts, generateUid) {
   var mutatorMap = {};
 
   node.properties = node.properties.filter(function (prop) {
@@ -20,8 +20,11 @@ exports.ObjectExpression = function (node) {
 
   if (_.isEmpty(mutatorMap)) return;
 
+  var objId = b.identifier(generateUid("ref"))
+
   return util.template("object-define-properties-closure", {
+    KEY: objId,
     OBJECT: node,
-    CONTENT: util.buildDefineProperties(mutatorMap, b.identifier("obj")).expression
+    CONTENT: util.buildDefineProperties(mutatorMap, objId).expression
   });
 };
diff --git a/lib/6to5/traverse/index.js b/lib/6to5/traverse/index.js
index de00dbd76b..6f125ea95e 100644
--- a/lib/6to5/traverse/index.js
+++ b/lib/6to5/traverse/index.js
@@ -11,7 +11,9 @@ var traverse = module.exports = function (parent, callbacks, blacklistTypes) {
     return;
   }
 
-  var keys = VISITOR_KEYS[parent.type] || [];
+  var keys = VISITOR_KEYS[parent.type];
+  if (!keys) return;
+
   blacklistTypes = blacklistTypes || [];
 
   if (_.isFunction(callbacks)) {
diff --git a/test/fixtures/syntax/computed-property-names/method/expected.js b/test/fixtures/syntax/computed-property-names/method/expected.js
index 983da7e15b..e229295c5b 100644
--- a/test/fixtures/syntax/computed-property-names/method/expected.js
+++ b/test/fixtures/syntax/computed-property-names/method/expected.js
@@ -1,6 +1,6 @@
-var obj = function (obj) {
-  obj[foobar] = function () {
+var obj = function (_ref) {
+  _ref[foobar] = function () {
     return "foobar";
   };
-  return obj;
+  return _ref;
 }({});
diff --git a/test/fixtures/syntax/computed-property-names/mixed/expected.js b/test/fixtures/syntax/computed-property-names/mixed/expected.js
index 706bd93908..5553d0d9ff 100644
--- a/test/fixtures/syntax/computed-property-names/mixed/expected.js
+++ b/test/fixtures/syntax/computed-property-names/mixed/expected.js
@@ -1,7 +1,7 @@
-var obj = function (obj) {
-  obj["x" + foo] = "heh";
-  obj["y" + bar] = "noo";
-  return obj;
+var obj = function (_ref) {
+  _ref["x" + foo] = "heh";
+  _ref["y" + bar] = "noo";
+  return _ref;
 }({
   foo: "foo",
   bar: "bar"
diff --git a/test/fixtures/syntax/computed-property-names/multiple/expected.js b/test/fixtures/syntax/computed-property-names/multiple/expected.js
index 394266087c..81c11f23f2 100644
--- a/test/fixtures/syntax/computed-property-names/multiple/expected.js
+++ b/test/fixtures/syntax/computed-property-names/multiple/expected.js
@@ -1,5 +1,5 @@
-var obj = function (obj) {
-  obj["x" + foo] = "heh";
-  obj["y" + bar] = "noo";
-  return obj;
+var obj = function (_ref) {
+  _ref["x" + foo] = "heh";
+  _ref["y" + bar] = "noo";
+  return _ref;
 }({});
diff --git a/test/fixtures/syntax/computed-property-names/single/expected.js b/test/fixtures/syntax/computed-property-names/single/expected.js
index d71682a31a..52a86de647 100644
--- a/test/fixtures/syntax/computed-property-names/single/expected.js
+++ b/test/fixtures/syntax/computed-property-names/single/expected.js
@@ -1,4 +1,4 @@
-var obj = function (obj) {
-  obj["x" + foo] = "heh";
-  return obj;
+var obj = function (_ref) {
+  _ref["x" + foo] = "heh";
+  return _ref;
 }({});
diff --git a/test/fixtures/syntax/computed-property-names/this/expected.js b/test/fixtures/syntax/computed-property-names/this/expected.js
index e1aee4c417..7d26e193a7 100644
--- a/test/fixtures/syntax/computed-property-names/this/expected.js
+++ b/test/fixtures/syntax/computed-property-names/this/expected.js
@@ -1,4 +1,4 @@
-var obj = function (obj) {
-  obj["x" + this.foo] = "heh";
-  return obj;
+var obj = function (_ref) {
+  _ref["x" + this.foo] = "heh";
+  return _ref;
 }.call(this, {});
diff --git a/test/fixtures/syntax/property-methods-assignment/getter-and-setter/expected.js b/test/fixtures/syntax/property-methods-assignment/getter-and-setter/expected.js
index d52c634e98..fc86c1cb17 100644
--- a/test/fixtures/syntax/property-methods-assignment/getter-and-setter/expected.js
+++ b/test/fixtures/syntax/property-methods-assignment/getter-and-setter/expected.js
@@ -1,5 +1,5 @@
-var obj = function (obj) {
-  Object.defineProperties(obj, {
+var obj = function (_ref) {
+  Object.defineProperties(_ref, {
     foo: {
       get: function () {
         return 5 + 5;
@@ -9,5 +9,5 @@ var obj = function (obj) {
       }
     }
   });
-  return obj;
+  return _ref;
 }({});
diff --git a/test/fixtures/syntax/property-methods-assignment/getter/expected.js b/test/fixtures/syntax/property-methods-assignment/getter/expected.js
index 7f6b975474..ea416a652a 100644
--- a/test/fixtures/syntax/property-methods-assignment/getter/expected.js
+++ b/test/fixtures/syntax/property-methods-assignment/getter/expected.js
@@ -1,10 +1,10 @@
-var obj = function (obj) {
-  Object.defineProperties(obj, {
+var obj = function (_ref) {
+  Object.defineProperties(_ref, {
     foo: {
       get: function () {
         return 5 + 5;
       }
     }
   });
-  return obj;
+  return _ref;
 }({});
diff --git a/test/fixtures/syntax/property-methods-assignment/setter/expected.js b/test/fixtures/syntax/property-methods-assignment/setter/expected.js
index 2bed21387e..b1329408d4 100644
--- a/test/fixtures/syntax/property-methods-assignment/setter/expected.js
+++ b/test/fixtures/syntax/property-methods-assignment/setter/expected.js
@@ -1,10 +1,10 @@
-var obj = function (obj) {
-  Object.defineProperties(obj, {
+var obj = function (_ref) {
+  Object.defineProperties(_ref, {
     foo: {
       set: function (value) {
         this._foo = value;
       }
     }
   });
-  return obj;
+  return _ref;
 }({});