gin test - add simple file access for JS

gin/test/file.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 "gin/test/file.h"
+
+#include <iostream>
+
+#include "base/bind.h"
+#include "base/file_util.h"
+#include "base/files/file_enumerator.h"
+#include "base/files/file_path.h"
+#include "base/path_service.h"
+#include "gin/arguments.h"
+#include "gin/converter.h"
+#include "gin/object_template_builder.h"
+#include "gin/per_isolate_data.h"
+#include "gin/public/wrapper_info.h"
+
+using v8::ObjectTemplate;
+
+namespace gin {
+
+namespace {
+
+v8::Handle<v8::Value> ReadFileToString(gin::Arguments* args) {
+  std::string filename;
+  if (!args->GetNext(&filename))
+    return v8::Null(args->isolate());
+
+  const base::FilePath& path = base::FilePath::FromUTF8Unsafe(filename);
+  std::string contents;
+  if (!ReadFileToString(path, &contents))
+    return v8::Null(args->isolate());
+
+  return gin::Converter<std::string>::ToV8(args->isolate(), contents);

[abarth-chromium, 2014/07/27 03:26:47]

You should be able to make the return type of this function std::string and then
just return contents.

[hansmuller, 2014/07/28 16:44:59]

I'm returning JS null when no filename is specified or the file doesn't exist. I
don't know of a way to do that if the function just returns std::string?

Likewise for the other two file functions.

Note also: I added some tests to check the null cases.

+}
+
+v8::Handle<v8::Value> GetSourceRootDirectory(v8::Isolate* isolate) {
+  base::FilePath path;
+  if (!PathService::Get(base::DIR_SOURCE_ROOT, &path))
+    return v8::Null(isolate);
+  return gin::Converter<std::string>::ToV8(isolate, path.AsUTF8Unsafe());

[abarth-chromium, 2014/07/27 03:26:47]

Ditto

+}
+
+v8::Handle<v8::Value> GetFilesInDirectory(gin::Arguments* args) {
+  std::string filename;
+  if (!args->GetNext(&filename))
+    return v8::Null(args->isolate());
+
+  const base::FilePath& path = base::FilePath::FromUTF8Unsafe(filename);
+  std::vector<std::string> names;
+  base::FileEnumerator e(path, false, base::FileEnumerator::FILES);
+  for (base::FilePath name = e.Next(); !name.empty(); name = e.Next()) {
+    names.push_back(name.BaseName().AsUTF8Unsafe());
+  }
+
+  return gin::Converter<std::vector<std::string>>::ToV8(args->isolate(), names);

[abarth-chromium, 2014/07/27 03:26:47]

Ditto

+}
+
+gin::WrapperInfo g_wrapper_info = { gin::kEmbedderNativeGin };
+
+}  // namespace
+
+const char File::kModuleName[] = "file";
+
+v8::Local<v8::Value> File::GetModule(v8::Isolate* isolate) {
+  gin::PerIsolateData* data = gin::PerIsolateData::From(isolate);
+  v8::Local<ObjectTemplate> templ = data->GetObjectTemplate(&g_wrapper_info);
+  if (templ.IsEmpty()) {
+    templ = gin::ObjectTemplateBuilder(isolate)
+        .SetMethod("readFileToString", ReadFileToString)
+        .SetMethod("getFilesInDirectory", GetFilesInDirectory)
+        .SetMethod("getSourceRootDirectory",
+                   base::Bind(GetSourceRootDirectory, isolate))

[abarth-chromium, 2014/07/27 03:26:47]

There's no reason to base::Bind here.  gin::Arguments contains the isolate.

[hansmuller, 2014/07/28 16:44:59]

OK.

+        .Build();
+    data->SetObjectTemplate(&g_wrapper_info, templ);
+  }
+  return templ->NewInstance();
+}
+
+}  // namespace gin