1 files changed, 29 insertions, 0 deletions
diff --git a/js/src/tests/non262/destructuring/rest-parameter-spread-call-optimization.js b/js/src/tests/non262/destructuring/rest-parameter-spread-call-optimization.js
new file mode 100644
index 0000000000..20f6a529dc
--- /dev/null
+++ b/js/src/tests/non262/destructuring/rest-parameter-spread-call-optimization.js
@@ -0,0 +1,29 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Ensure the spread-call optimization doesn't break when a destructuring rest
+// parameter is used.
+
+function spreadTarget() { return arguments.length; }
+
+function spreadOpt(...[r]){ return spreadTarget(...r); }
+assertEq(spreadOpt([]), 0);
+assertEq(spreadOpt([10]), 1);
+assertEq(spreadOpt([10, 20]), 2);
+assertEq(spreadOpt([10, 20, 30]), 3);
+
+function spreadOpt2(...[...r]){ return spreadTarget(...r); }
+assertEq(spreadOpt2(), 0);
+assertEq(spreadOpt2(10), 1);
+assertEq(spreadOpt2(10, 20), 2);
+assertEq(spreadOpt2(10, 20, 30), 3);
+
+function spreadOpt3(r, ...[]){ return spreadTarget(...r); }
+assertEq(spreadOpt3([]), 0);
+assertEq(spreadOpt3([10]), 1);
+assertEq(spreadOpt3([10, 20]), 2);
+assertEq(spreadOpt3([10, 20, 30]), 3);
+
+if (typeof reportCompare === "function")
+    reportCompare(0, 0);