diff -r 000000000000 -r 6474c204b198 js/src/jsapi-tests/testOOM.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jsapi-tests/testOOM.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,81 @@
+/* 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/. */
+
+#include "mozilla/DebugOnly.h"
+
+#include "jsapi-tests/tests.h"
+
+BEGIN_TEST(testOOM)
+{
+    JS::RootedValue v(cx, JS::Int32Value(9));
+    JS::RootedString jsstr(cx, JS::ToString(cx, v));
+    mozilla::DebugOnly<const jschar *> s = JS_GetStringCharsZ(cx, jsstr);
+    JS_ASSERT(s[0] == '9' && s[1] == '\0');
+    return true;
+}
+
+virtual JSRuntime * createRuntime()
+{
+    JSRuntime *rt = JS_NewRuntime(0, JS_USE_HELPER_THREADS);
+    if (!rt)
+        return nullptr;
+    JS_SetGCParameter(rt, JSGC_MAX_BYTES, (uint32_t)-1);
+    setNativeStackQuota(rt);
+    return rt;
+}
+END_TEST(testOOM)
+
+#ifdef DEBUG  // OOM_maxAllocations is only available in debug builds.
+
+const uint32_t maxAllocsPerTest = 100;
+
+#define START_OOM_TEST(name)                                                  \
+    testName = name;                                                          \
+    printf("Test %s: started\n", testName);                                   \
+    for (oomAfter = 1; oomAfter < maxAllocsPerTest; ++oomAfter) {             \
+        setOOMAfter(oomAfter)
+
+#define OOM_TEST_FINISHED                                                     \
+    {                                                                         \
+        printf("Test %s: finished with %d allocations\n",                     \
+               testName, oomAfter - 1);                                       \
+        break;                                                                \
+    }
+
+#define END_OOM_TEST                                                          \
+    }                                                                         \
+    cancelOOMAfter();                                                         \
+    CHECK(oomAfter != maxAllocsPerTest)
+
+BEGIN_TEST(testNewRuntime)
+{
+    uninit(); // Get rid of test harness' original JSRuntime.
+
+    JSRuntime *rt;
+    START_OOM_TEST("new runtime");
+    rt = JS_NewRuntime(8L * 1024 * 1024, JS_USE_HELPER_THREADS);
+    if (rt)
+        OOM_TEST_FINISHED;
+    END_OOM_TEST;
+    JS_DestroyRuntime(rt);
+    return true;
+}
+
+const char* testName;
+uint32_t oomAfter;
+
+void
+setOOMAfter(uint32_t numAllocs)
+{
+    OOM_maxAllocations = OOM_counter + numAllocs;
+}
+
+void
+cancelOOMAfter()
+{
+    OOM_maxAllocations = UINT32_MAX;
+}
+END_TEST(testNewRuntime)
+
+#endif