Plumb commandline arguments for mojo_example_apptests.

mojo/examples/apptest/example_apptest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/examples/apptest/example_client_application.h"
 #include "mojo/examples/apptest/example_client_impl.h"
 #include "mojo/examples/apptest/example_service.mojom.h"
 #include "mojo/public/c/system/main.h"
 #include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/bindings/callback.h"
 #include "mojo/public/cpp/environment/environment.h"
 #include "mojo/public/cpp/system/macros.h"
 #include "mojo/public/cpp/utility/run_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 // TODO(msw): Remove this once we can get ApplicationImpl from TLS.
 mojo::ApplicationImpl* g_application_impl_hack = NULL;
 
+static const char kMojoExampleService[] = "mojo:mojo_example_service";
+
 }  // namespace
 
 namespace mojo {
 
 namespace {
 
 class ExampleApptest : public testing::Test {
  public:
   ExampleApptest() {
-    g_application_impl_hack->ConnectToService("mojo:mojo_example_service",
+    g_application_impl_hack->ConnectToService(kMojoExampleService,
                                               &example_service_);
     example_service_.set_client(&example_client_);
   }
 
   virtual ~ExampleApptest() override {}
 
  protected:
   ExampleServicePtr example_service_;
   ExampleClientImpl example_client_;
 
@@ skipping 41 matching lines @@
 MojoResult MojoMain(MojoHandle shell_handle) {
   mojo::Environment env;
   // TODO(msw): Destroy this ambient RunLoop before running tests.
   //            Need to CancelWait() / PassMessagePipe() from the ShellPtr?
   mojo::RunLoop loop;
   mojo::ApplicationDelegate* delegate = new mojo::ExampleClientApplication();
   mojo::ApplicationImpl app(delegate, shell_handle);
   g_application_impl_hack = &app;
   MOJO_CHECK(app.WaitForInitialize());
 
-  // TODO(msw): Plumb commandline arguments through app->args().
-  int argc = 0;
-  char** argv = NULL;
-  testing::InitGoogleTest(&argc, argv);
+  std::vector<std::string> args = app.args().To<std::vector<std::string> >();
+  int argc = args.size();
+  std::vector<char *> argv(argc);
+  for (int i = 0; i < argc; ++i)

[hansmuller, 2014/10/06 21:08:52]

You might want to use size_t instead of int for the loop index etc.

I don't think you need to convert the Mojo args array to a std::vector, you
should be able to copy app.args() into the GTest (mutable) argv roughly like
this:

  for (size_t i = 0; i < argc; ++)
    argv[i] = app.args()[i].data();

[msw, 2014/10/06 21:32:33]

InitGoogleTest eventually requires an int* :-/
I don't think that'll work, because InitGoogleTest has the baffling behavior of
removing GTEST arguments from |argv| and decrementing |argc|, so this can't pass
the App's const string data directly. lmk if I'm missing something.

+    argv[i] = &args[i][0];
+  testing::InitGoogleTest(&argc, argv.data());
+
   mojo_ignore_result(RUN_ALL_TESTS());
 
   delete delegate;
   return MOJO_RESULT_OK;
 }