don't unpack array when the pattern contains more elements than the corresponding array expression

This commit is contained in:
Sebastian McKenzie 2015-02-22 22:35:38 +11:00
parent c3c94f0a4a
commit 0b2f1fedcb

View File

@ -168,6 +168,7 @@ DestructuringTransformer.prototype.canUnpackArrayPattern = function (pattern, ar
// pattern has less elements than the array and doesn't have a rest so some
// elements wont be evaluated
if (pattern.elements.length > arr.elements.length) return;
if (pattern.elements.length < arr.elements.length && !hasRest(pattern)) return false;
// deopt on holes
@ -418,7 +419,7 @@ exports.AssignmentExpression = function (node, parent, scope, file) {
return t.toSequenceExpression(nodes, scope);
};
var variableDeclarationhasPattern = function (node) {
var variableDeclarationHasPattern = function (node) {
for (var i = 0; i < node.declarations.length; i++) {
if (t.isPattern(node.declarations[i].id)) {
return true;
@ -429,7 +430,7 @@ var variableDeclarationhasPattern = function (node) {
exports.VariableDeclaration = function (node, parent, scope, file) {
if (t.isForInStatement(parent) || t.isForOfStatement(parent)) return;
if (!variableDeclarationhasPattern(node)) return;
if (!variableDeclarationHasPattern(node)) return;
var nodes = [];
var declar;