Implement Mojo message codec in JavaScript

mojo/public/bindings/js/test/run_js_tests.cc

 // Copyright 2013 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 "base/file_util.h"
 #include "base/path_service.h"
 #include "gin/modules/module_registry.h"
 #include "gin/test/file_runner.h"
 #include "gin/test/gtest.h"
 #include "mojo/public/bindings/js/runner_delegate.h"
@@ skipping 26 matching lines @@
              .AppendASCII(test);
   TestRunnerDelegate delegate;
   gin::RunTestFromFile(path, &delegate);
 }
 
 // TODO(abarth): Should we autogenerate these stubs from GYP?
 TEST(JSTest, core) {
   RunTest("core_unittests.js");
 }
 
+TEST(JSTest, codec) {
+  // TODO(abarth): Rather than loading all these files manually, we should
+  // teach the module loading system how to find imported modules on disk.

[abarth-chromium, 2013/11/17 20:07:05]

This code will get much cleaner once https://codereview.chromium.org/74753002/
lands and I rebase over it.  However, I'm leaving this CL in its current state
so the two can land independently.

+
+  base::FilePath path;
+  PathService::Get(base::DIR_SOURCE_ROOT, &path);
+  path = path.AppendASCII("mojo")
+             .AppendASCII("public")
+             .AppendASCII("bindings")
+             .AppendASCII("js");
+
+  base::FilePath codec_path = path.AppendASCII("codec.js");
+  ASSERT_TRUE(base::PathExists(codec_path))
+      << codec_path.LossyDisplayName();
+
+  base::FilePath codec_unittests_path = path.AppendASCII("codec_unittests.js");
+  ASSERT_TRUE(base::PathExists(codec_unittests_path))
+      << codec_unittests_path.LossyDisplayName();
+
+  base::FilePath sample_service_path =
+      path.AppendASCII("test").AppendASCII("sample_service.js");
+  ASSERT_TRUE(base::PathExists(sample_service_path))
+      << sample_service_path.LossyDisplayName();
+
+  std::string codec;
+  ASSERT_TRUE(ReadFileToString(codec_path, &codec));
+
+  std::string codec_unittests;
+  ASSERT_TRUE(ReadFileToString(codec_unittests_path, &codec_unittests));
+
+  std::string sample_service;
+  ASSERT_TRUE(ReadFileToString(sample_service_path, &sample_service));
+
+  TestRunnerDelegate delegate;
+  gin::RunTestFromString(codec + codec_unittests + sample_service, &delegate);
+}
+
 }  // namespace
 }  // namespace js
 }  // namespace mojo