1 files changed, 20 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/warp/guard-function-is-non-builtin-ctor.js b/js/src/jit-test/tests/warp/guard-function-is-non-builtin-ctor.js
new file mode 100644
index 0000000000..c2b92d4510
--- /dev/null
+++ b/js/src/jit-test/tests/warp/guard-function-is-non-builtin-ctor.js
@@ -0,0 +1,20 @@
+function test() {
+  for (var i = 0; i <= 200; ++i) {
+    // Create a fresh function in each iteration.
+    var values = [function(){}, () => {}];
+
+    // Use an arrow function in the last iteration.
+    var useArrowFn = (i === 200);
+
+    // No conditional (?:) so we don't trigger a cold-code bailout.
+    var value = values[0 + useArrowFn];
+
+    // Set or create the "prototype" property.
+    value.prototype = null;
+
+    // The "prototype" is configurable iff the function is an arrow function.
+    var desc = Object.getOwnPropertyDescriptor(value, "prototype");
+    assertEq(desc.configurable, useArrowFn);
+  }
+}
+test();