From de8b2fabb9f6b381ff271bb2a91f40f1c02a8561 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Tue, 12 May 2015 16:53:53 -0700
Subject: [PATCH] Optimize spread to not generate x.slice() when x is an array
 literal

---
 src/compiler/emitter.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/emitter.ts b/src/compiler/emitter.ts
index 37e1f231bcf..4c979486ff3 100644
--- a/src/compiler/emitter.ts
+++ b/src/compiler/emitter.ts
@@ -1383,7 +1383,7 @@ var __param = (this && this.__param) || function (paramIndex, decorator) {
                         e = (<SpreadElementExpression>e).expression;
                         emitParenthesizedIf(e, /*parenthesized*/ group === 0 && needsParenthesisForPropertyAccessOrInvocation(e));
                         pos++;
-                        if (pos === length && group === 0 && alwaysCopy) {
+                        if (pos === length && group === 0 && alwaysCopy && e.kind !== SyntaxKind.ArrayLiteralExpression) {
                             write(".slice()");
                         }
                     }