1 files changed, 32 insertions, 0 deletions
diff --git a/xpcom/tests/unit/test_debugger_malloc_size_of.js b/xpcom/tests/unit/test_debugger_malloc_size_of.js
new file mode 100644
index 0000000000..3141d8c2c3
--- /dev/null
+++ b/xpcom/tests/unit/test_debugger_malloc_size_of.js
@@ -0,0 +1,32 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* 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/. */
+
+// This is just a sanity test that Gecko is giving SpiderMonkey a MallocSizeOf
+// function for new JSRuntimes. There is more extensive testing around the
+// expected byte sizes within SpiderMonkey's jit-tests, we just want to make
+// sure that Gecko is providing SpiderMonkey with the callback it needs.
+
+const { byteSize } = Cu.getJSTestingFunctions();
+
+function run_test() {
+  const objects = [
+    {},
+    { w: 1, x: 2, y: 3, z: 4, a: 5 },
+    [],
+    Array(10).fill(null),
+    new RegExp("(2|two) problems", "g"),
+    new Date(),
+    new Uint8Array(64),
+    Promise.resolve(1),
+    function f() {},
+    Object,
+  ];
+
+  for (let obj of objects) {
+    info(uneval(obj));
+    ok(byteSize(obj), "We should get some (non-zero) byte size");
+  }
+}