diff -r 000000000000 -r 6474c204b198 xpcom/tests/TestRegistrationOrder.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/tests/TestRegistrationOrder.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,194 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 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/. */
+
+#include "TestHarness.h"
+#include "nsIFile.h"
+#include "nsIDirectoryService.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsCOMArray.h"
+#include "nsArrayEnumerator.h"
+#include "nsXULAppAPI.h"
+#include "nsIComponentRegistrar.h"
+
+#define SERVICE_A_CONTRACT_ID  "@mozilla.org/RegTestServiceA;1"
+#define SERVICE_B_CONTRACT_ID  "@mozilla.org/RegTestServiceB;1"
+
+// {56ab1cd4-ac44-4f86-8104-171f8b8f2fc7}
+#define CORE_SERVICE_A_CID             \
+        { 0x56ab1cd4, 0xac44, 0x4f86, \
+        { 0x81, 0x04, 0x17, 0x1f, 0x8b, 0x8f, 0x2f, 0xc7} }
+NS_DEFINE_CID(kCoreServiceA_CID, CORE_SERVICE_A_CID);
+
+// {fe64efb7-c5ab-41a6-b639-e6c0f483181e}
+#define EXT_SERVICE_A_CID             \
+        { 0xfe64efb7, 0xc5ab, 0x41a6, \
+        { 0xb6, 0x39, 0xe6, 0xc0, 0xf4, 0x83, 0x18, 0x1e} }
+NS_DEFINE_CID(kExtServiceA_CID, EXT_SERVICE_A_CID);
+
+// {d04d1298-6dac-459b-a13b-bcab235730a0}
+#define CORE_SERVICE_B_CID             \
+        { 0xd04d1298, 0x6dac, 0x459b, \
+        { 0xa1, 0x3b, 0xbc, 0xab, 0x23, 0x57, 0x30, 0xa0 } }
+NS_DEFINE_CID(kCoreServiceB_CID, CORE_SERVICE_B_CID);
+
+// {e93dadeb-a6f6-4667-bbbc-ac8c6d440b20}
+#define EXT_SERVICE_B_CID             \
+        { 0xe93dadeb, 0xa6f6, 0x4667, \
+        { 0xbb, 0xbc, 0xac, 0x8c, 0x6d, 0x44, 0x0b, 0x20 } }
+NS_DEFINE_CID(kExtServiceB_CID, EXT_SERVICE_B_CID);
+
+nsresult execRegOrderTest(const char *aTestName, const char *aContractID,
+                      const nsCID &aCoreCID, const nsCID &aExtCID)
+{
+  // Make sure the core service loaded (it won't be found using contract ID).
+  nsresult rv = NS_ERROR_FAILURE;
+  nsCOMPtr<nsISupports> coreService = do_CreateInstance(aCoreCID, &rv);
+#ifdef DEBUG_brade
+  if (rv) fprintf(stderr, "rv: %d (%x)\n", rv, rv);
+  fprintf(stderr, "coreService: %p\n", coreService.get());
+#endif
+  if (NS_FAILED(rv))
+  {
+    fail("%s FAILED - cannot create core service\n", aTestName);
+    return rv;
+  }
+
+  // Get the extension service.
+  nsCOMPtr<nsISupports> extService = do_CreateInstance(aExtCID, &rv);
+#ifdef DEBUG_brade
+  if (rv) fprintf(stderr, "rv: %d (%x)\n", rv, rv);
+  fprintf(stderr, "extService: %p\n", extService.get());
+#endif
+  if (NS_FAILED(rv))
+  {
+    fail("%s FAILED - cannot create extension service\n", aTestName);
+    return rv;
+  }
+
+  /*
+   * Get the service by contract ID and make sure it is the extension
+   * service (it should be, since the extension directory was registered
+   * after the core one).
+   */
+  nsCOMPtr<nsISupports> service = do_CreateInstance(aContractID, &rv);
+#ifdef DEBUG_brade
+  if (rv) fprintf(stderr, "rv: %d (%x)\n", rv, rv);
+  fprintf(stderr, "service: %p\n", service.get());
+#endif
+  if (NS_FAILED(rv))
+  {
+    fail("%s FAILED - cannot create service\n", aTestName);
+    return rv;
+  }
+
+  if (service != extService)
+  {
+    fail("%s FAILED - wrong service registered\n", aTestName);
+    return NS_ERROR_FAILURE;
+  }
+
+  passed(aTestName);
+  return NS_OK;
+}
+
+nsresult TestRegular()
+{
+  return execRegOrderTest("TestRegular", SERVICE_A_CONTRACT_ID,
+                          kCoreServiceA_CID, kExtServiceA_CID);
+}
+
+nsresult TestJar()
+{
+  return execRegOrderTest("TestJar", SERVICE_B_CONTRACT_ID,
+                          kCoreServiceB_CID, kExtServiceB_CID);
+}
+
+bool TestContractFirst()
+{
+  nsCOMPtr<nsIComponentRegistrar> r;
+  NS_GetComponentRegistrar(getter_AddRefs(r));
+
+  nsCID* cid = nullptr;
+  nsresult rv = r->ContractIDToCID("@mozilla.org/RegTestOrderC;1", &cid);
+  if (NS_FAILED(rv)) {
+    fail("RegTestOrderC: contract not registered");
+    return false;
+  }
+
+  nsCID goodcid;
+  goodcid.Parse("{ada15884-bb89-473c-8b50-dcfbb8447ff4}");
+
+  if (!goodcid.Equals(*cid)) {
+    fail("RegTestOrderC: CID doesn't match");
+    return false;
+  }
+
+  passed("RegTestOrderC");
+  return true;
+}
+
+static already_AddRefed<nsIFile>
+GetRegDirectory(const char* basename, const char* dirname, const char* leafname)
+{
+    nsCOMPtr<nsIFile> f;
+    nsresult rv = NS_NewNativeLocalFile(nsDependentCString(basename), true,
+                                        getter_AddRefs(f));
+    if (NS_FAILED(rv))
+        return nullptr;
+
+    f->AppendNative(nsDependentCString(dirname));
+    if (leafname)
+        f->AppendNative(nsDependentCString(leafname));
+    return f.forget();
+}
+
+
+
+int main(int argc, char** argv)
+{
+  if (argc < 2)
+  {
+    fprintf(stderr, "not enough arguments -- need registration dir path\n");
+    return 1;
+  }
+
+  ScopedLogging logging;
+
+#ifdef XP_WIN
+  // On Windows, convert to backslashes
+  size_t regPathLen = strlen(argv[1]);
+  char* regPath = new char[regPathLen + 1];
+  for (size_t i = 0; i < regPathLen; i++) {
+    char curr = argv[1][i];
+    regPath[i] = (curr == '/') ? '\\' : curr;
+  }
+  regPath[regPathLen] = '\0';
+#else
+  const char *regPath = argv[1];
+#endif
+
+  XRE_AddManifestLocation(NS_COMPONENT_LOCATION,
+                          nsCOMPtr<nsIFile>(GetRegDirectory(regPath, "core", "component.manifest")));
+  XRE_AddManifestLocation(NS_COMPONENT_LOCATION,
+                          nsCOMPtr<nsIFile>(GetRegDirectory(regPath, "extension", "extComponent.manifest")));
+  XRE_AddJarManifestLocation(NS_COMPONENT_LOCATION,
+                          nsCOMPtr<nsIFile>(GetRegDirectory(regPath, "extension2.jar", nullptr)));
+  ScopedXPCOM xpcom("RegistrationOrder");
+  if (xpcom.failed())
+    return 1;
+
+  int rv = 0;
+  if (NS_FAILED(TestRegular()))
+    rv = 1;
+
+  if (NS_FAILED(TestJar()))
+    rv = 1;
+
+  if (!TestContractFirst())
+    rv = 1;
+
+  return rv;
+}