added support for default arguments

fixes #2622

lib/Parser.js

@@ -873,6 +873,7 @@ Parser.prototype.walkIdentifier = function walkIdentifier(expression) {
 
 Parser.prototype.inScope = function inScope(params, fn) {
 	var oldScope = this.scope;
+	var _this = this;
 	this.scope = {
 		inTry: false,
 		inShorthand: false,
@@ -881,15 +882,51 @@ Parser.prototype.inScope = function inScope(params, fn) {
 	};
 	params.forEach(function(param) {
 		if(typeof param !== "string") {
-			if(param.type !== "Identifier")
-				return;
-			param = param.name;
+			param = _this.enterPattern(param, function(param) {
+				_this.scope.renames["$" + param] = undefined;
+				_this.scope.definitions.push(param);
+			});
+		} else {
+			_this.scope.renames["$" + param] = undefined;
+			_this.scope.definitions.push(param);
 		}
-		this.scope.renames["$" + param] = undefined;
-		this.scope.definitions.push(param);
-	}, this);
+	});
 	fn();
-	this.scope = oldScope;
+	_this.scope = oldScope;
+};
+
+Parser.prototype.enterPattern = function enterPattern(pattern, onIdent) {
+	if(this["enter" + pattern.type])
+		return this["enter" + pattern.type](pattern, onIdent);
+};
+
+Parser.prototype.enterIdentifier = function enterIdentifier(pattern, onIdent) {
+	onIdent(pattern.name);
+};
+
+Parser.prototype.enterObjectPattern = function enterObjectPattern(pattern, onIdent) {
+	pattern.properties.forEach(function(property) {
+		switch(property.type) {
+			case "AssignmentProperty":
+				this.enterPattern(property.value, onIdent);
+				break;
+		}
+	}, this);
+};
+
+Parser.prototype.enterArrayPattern = function enterArrayPattern(pattern, onIdent) {
+	pattern.elements.forEach(function(pattern) {
+		this.enterPattern(pattern, onIdent);
+	}, this);
+};
+
+Parser.prototype.enterRestElement = function enterRestElement(pattern, onIdent) {
+	this.enterPattern(pattern.argument, onIdent);
+};
+
+Parser.prototype.enterAssignmentPattern = function enterAssignmentPattern(pattern, onIdent) {
+	this.enterPattern(pattern.left, onIdent);
+	this.walkExpression(pattern.right);
 };
 
 Parser.prototype.evaluateExpression = function evaluateExpression(expression) {

package.json

@@ -4,7 +4,7 @@
   "author": "Tobias Koppers @sokra",
   "description": "Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.",
   "dependencies": {
-    "acorn": "^3.0.0",
+    "acorn": "^3.2.0",
     "async": "^1.3.0",
     "clone": "^1.0.2",
     "enhanced-resolve": "^2.2.0",

test/cases/parsing/issue-2622/index.js

@@ -0,0 +1,16 @@
+import { a, b } from "./module";
+
+function func(x = a, y = b) {
+	return [x, y];
+}
+
+var func2 = function(x = a, y = b) {
+	return [x, y];
+}
+
+it("should import into default parameters", function() {
+	func().should.be.eql(["a", "b"]);
+	func2().should.be.eql(["a", "b"]);
+	func(1).should.be.eql([1, "b"]);
+	func2(2).should.be.eql([2, "b"]);
+});

test/cases/parsing/issue-2622/module.js

@@ -0,0 +1,2 @@
+export var a = "a";
+export var b = "b";

test/cases/parsing/issue-2622/test.filter.js

@@ -0,0 +1,5 @@
+var supportsDefaultArgs = require("../../../helpers/supportsDefaultArgs");
+
+module.exports = function(config) {
+	return !config.minimize && supportsDefaultArgs();
+};

test/helpers/supportsDefaultArgs.js

@@ -0,0 +1,8 @@
+module.exports = function supportsDefaultArgs() {
+	try {
+		var f = eval("(function f(a = 123) { return a; })");
+		return f() === 123;
+	} catch(e) {
+		return false;
+	}
+};