Merge pull request webpack#3250 from Kovensky/issue-3238

sokra · web-flow · commit bbd6eb77e9aa · 2016-11-08T17:39:50.000+01:00
Fix issue webpack#3238
diff --git a/lib/Parser.js b/lib/Parser.js
@@ -909,7 +909,7 @@ Parser.prototype.inScope = function inScope(params, fn) {
 };
 
 Parser.prototype.enterPattern = function enterPattern(pattern, onIdent) {
-	if(this["enter" + pattern.type])
+	if(pattern != null && this["enter" + pattern.type])
 		return this["enter" + pattern.type](pattern, onIdent);
 };
 
diff --git a/test/cases/parsing/issue-3238/index.js b/test/cases/parsing/issue-3238/index.js
@@ -0,0 +1,4 @@
+it("supports empty element in destructuring", function() {
+  const second = ([, x]) => x;
+  second([1, 2]).should.eql(2);
+});
diff --git a/test/cases/parsing/issue-3238/test.filter.js b/test/cases/parsing/issue-3238/test.filter.js
@@ -0,0 +1,5 @@
+var supportsIteratorDestructuring = require("../../../helpers/supportsIteratorDestructuring");
+
+module.exports = function(config) {
+	return !config.minimize && supportsIteratorDestructuring();
+};
diff --git a/test/helpers/supportsIteratorDestructuring.js b/test/helpers/supportsIteratorDestructuring.js
@@ -0,0 +1,8 @@
+module.exports = function supportsIteratorDestructuring() {
+	try {
+		var f = eval("(function f([, x, ...y]) { return x; })");
+		return f([1, 2]) === 2;
+	} catch(e) {
+		return false;
+	}
+};
