Make JSONParser a pure interface.

components/safe_json/safe_json_parser.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 "components/safe_json/safe_json_parser.h"
 
-#include <string>
-
-#include "base/single_thread_task_runner.h"
-#include "base/strings/utf_string_conversions.h"
-#include "base/thread_task_runner_handle.h"
-#include "base/tuple.h"
-#include "base/values.h"
-#include "components/safe_json/safe_json_parser_messages.h"
-#include "content/public/browser/browser_thread.h"
-#include "content/public/browser/utility_process_host.h"
-#include "grit/components_strings.h"
-#include "ipc/ipc_message_macros.h"
-#include "ui/base/l10n/l10n_util.h"
-
-using content::BrowserThread;
-using content::UtilityProcessHost;
+#include "components/safe_json/safe_json_parser_impl.h"
 
 namespace safe_json {
 
-SafeJsonParser::SafeJsonParser(const std::string& unsafe_json,
-                               const SuccessCallback& success_callback,
-                               const ErrorCallback& error_callback)
-    : unsafe_json_(unsafe_json),
-      success_callback_(success_callback),
-      error_callback_(error_callback) {
+namespace {
+
+SafeJsonParser::Factory g_factory = nullptr;
+
+}  // namespace
+
+// static
+void SafeJsonParser::SetFactoryForTesting(Factory factory) {
+  g_factory = factory;
 }
 
-void SafeJsonParser::Start() {
-  caller_task_runner_ = base::ThreadTaskRunnerHandle::Get();
-
-  BrowserThread::PostTask(
-      BrowserThread::IO, FROM_HERE,
-      base::Bind(&SafeJsonParser::StartWorkOnIOThread, this));
-}
-
-SafeJsonParser::~SafeJsonParser() {
-}
-
-void SafeJsonParser::StartWorkOnIOThread() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  UtilityProcessHost* host = UtilityProcessHost::Create(
-      this, base::ThreadTaskRunnerHandle::Get().get());
-  host->SetName(
-      l10n_util::GetStringUTF16(IDS_UTILITY_PROCESS_JSON_PARSER_NAME));
-  host->Send(new SafeJsonParserMsg_ParseJSON(unsafe_json_));
-}
-
-void SafeJsonParser::OnJSONParseSucceeded(const base::ListValue& wrapper) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  const base::Value* value = NULL;
-  CHECK(wrapper.Get(0, &value));
-
-  parsed_json_.reset(value->DeepCopy());
-  ReportResults();
-}
-
-void SafeJsonParser::OnJSONParseFailed(const std::string& error_message) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  error_ = error_message;
-  ReportResults();
-}
-
-void SafeJsonParser::ReportResults() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-
-  caller_task_runner_->PostTask(
-      FROM_HERE,
-      base::Bind(&SafeJsonParser::ReportResultsOnOriginThread, this));
-}
-
-void SafeJsonParser::ReportResultsOnOriginThread() {
-  // Current callers of this class are known to either come from
-  // the UI or IO threads. This DCHECK can be removed/further enhanced
-  // in case this class is useable outside of these contexts.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI) ||
-         BrowserThread::CurrentlyOn(BrowserThread::IO));
-  if (error_.empty() && parsed_json_) {
-    if (!success_callback_.is_null())
-      success_callback_.Run(parsed_json_.Pass());
-  } else {
-    if (!error_callback_.is_null())
-      error_callback_.Run(error_);
-  }
-}
-
-bool SafeJsonParser::OnMessageReceived(const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(SafeJsonParser, message)
-    IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Succeeded,
-                        OnJSONParseSucceeded)
-    IPC_MESSAGE_HANDLER(SafeJsonParserHostMsg_ParseJSON_Failed,
-                        OnJSONParseFailed)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
+// static
+void SafeJsonParser::Parse(const std::string& unsafe_json,
+                           const SuccessCallback& success_callback,
+                           const ErrorCallback& error_callback) {
+  SafeJsonParser* parser =
+      g_factory ? g_factory(unsafe_json, success_callback, error_callback)
+                : new SafeJsonParserImpl(unsafe_json, success_callback,
+                                         error_callback);
+  parser->Start();
 }
 
 }  // namespace safe_json