Merge branch 'esnext'

Conflicts:
	package.json

lib/6to5/transformation/templates/default-parameter.js

@@ -0,0 +1 @@
+var VARIABLE_NAME = ARGUMENTS[ARGUMENT_KEY] === undefined ? DEFAULT_VALUE : ARGUMENTS[ARGUMENT_KEY];

lib/6to5/transformation/templates/if-undefined-set-to.js

@@ -1 +0,0 @@
-if (VARIABLE === undefined) VARIABLE = DEFAULT;

lib/6to5/transformation/templates/object-define-properties-closure.js

@@ -0,0 +1,5 @@
+
+(function (KEY) {
+  CONTENT;
+  return KEY;
+})(OBJECT);

lib/6to5/transformation/transform.js

@@ -42,7 +42,6 @@ _.each({
   // spec
   specBlockHoistFunctions:   require("./transformers/spec-block-hoist-functions"),
   specNoForInOfAssignment:   require("./transformers/spec-no-for-in-of-assignment"),
-  specNoDuplicateProperties: require("./transformers/spec-no-duplicate-properties"),
 
   // playground
   methodBinding:             require("./transformers/playground-method-binding"),

lib/6to5/transformation/transformers/es6-default-parameters.js

@@ -49,16 +49,29 @@ exports.Function = function (node, parent, file, scope) {
 
   var body = [];
 
+  var argsIdentifier = t.identifier("arguments");
+  argsIdentifier._ignoreAliasFunctions = true;
+
+  var lastNonDefaultParam = 0;
+
   for (i in node.defaults) {
     def = node.defaults[i];
-    if (!def) continue;
+    if (!def) {
+      lastNonDefaultParam = +i + 1;
+      continue;
+    }
 
-    body.push(util.template("if-undefined-set-to", {
-      VARIABLE: node.params[i],
-      DEFAULT:  def
+    body.push(util.template("default-parameter", {
+      VARIABLE_NAME: node.params[i],
+      DEFAULT_VALUE: def,
+      ARGUMENT_KEY:  t.literal(+i),
+      ARGUMENTS:     argsIdentifier
     }, true));
   }
 
+  // we need to cut off all trailing default parameters
+  node.params = node.params.slice(0, lastNonDefaultParam);
+
   if (iife) {
     var container = t.functionExpression(null, [], node.body, node.generator);
     container._aliasFunction = true;

lib/6to5/transformation/transformers/es6-spread.js

@@ -83,6 +83,8 @@ exports.CallExpression = function (node, parent, file, scope) {
     if (temp) {
       callee.object = t.assignmentExpression("=", temp, callee.object);
       contextLiteral = temp;
+    } else {
+      contextLiteral = callee.object;
     }
     t.appendToMemberExpression(callee, t.identifier("apply"));
   } else {

lib/6to5/transformation/transformers/spec-no-duplicate-properties.js

@@ -1,25 +0,0 @@
-var t = require("../../types");
-
-exports.ObjectExpression = function (node, parent, file) {
-  var keys = [];
-
-  for (var i in node.properties) {
-    var prop = node.properties[i];
-    if (prop.computed || prop.kind !== "init") continue;
-
-    var key = prop.key;
-    if (t.isIdentifier(key)) {
-      key = key.name;
-    } else if (t.isLiteral(key)) {
-      key = key.value;
-    } else {
-      continue;
-    }
-
-    if (keys.indexOf(key) >= 0) {
-      throw file.errorWithNode(prop.key, "Duplicate property key");
-    } else {
-      keys.push(key);
-    }
-  }
-};

lib/6to5/traverse/scope.js

@@ -63,38 +63,29 @@ Scope.prototype.generateUidBasedOnNode = function (parent, file) {
     node = parent.left;
   } else if (t.isVariableDeclarator(parent)) {
     node = parent.id;
-  }
-
-  var id = "ref";
-
-  if (t.isProperty(node)) {
+  } else if (t.isProperty(node)) {
     node = node.key;
   }
 
-  if (t.isIdentifier(node)) {
-    id = node.name;
-  } else if (t.isLiteral(node)) {
-    id = node.value;
-  } else if (t.isMemberExpression(node)) {
-    var parts = [];
+  var parts = [];
 
-    var add = function (node) {
-      if (t.isMemberExpression(node)) {
-        add(node.object);
-        add(node.property);
-      } else if (t.isIdentifier(node)) {
-        parts.push(node.name);
-      } else if (t.isLiteral(node)) {
-        parts.push(node.value);
-      }
-    };
+  var add = function (node) {
+    if (t.isMemberExpression(node)) {
+      add(node.object);
+      add(node.property);
+    } else if (t.isIdentifier(node)) {
+      parts.push(node.name);
+    } else if (t.isLiteral(node)) {
+      parts.push(node.value);
+    } else if (t.isCallExpression(node)) {
+      add(node.callee);
+    }
+  };
 
-    add(node);
+  add(node);
 
-    id = parts.join("$");
-  }
-
-  id = id.replace(/^_/, "");
+  var id = parts.join("$");
+  id = id.replace(/^_/, "") || "ref";
 
   return file.generateUidIdentifier(id, this);
 };
@@ -108,10 +99,6 @@ Scope.prototype.generateUidBasedOnNode = function (parent, file) {
  */
 
 Scope.prototype.generateTempBasedOnNode = function (node, file) {
-  if (!t.isIdentifier(node) && !t.isMemberExpression(node)) {
-    throw new TypeError("Invalid node type " + JSON.stringify(node.type) + " passed to Scope.prototype.generateTempBasedOnNode");
-  }
-
   if (t.isIdentifier(node) && this.has(node.name, true)) {
     return null;
   }