Add InterestsFetcher which retrieves a user's interests from the server.

chrome/browser/interests/interests_retriever_unittest.cc

+// Copyright 2015 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 "chrome/browser/interests/interests_retriever.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/memory/ref_counted.h"
+#include "base/message_loop/message_loop.h"
+#include "base/thread_task_runner_handle.h"
+#include "net/base/net_errors.h"
+#include "net/http/http_status_code.h"
+#include "net/url_request/test_url_fetcher_factory.h"
+#include "net/url_request/url_request_status.h"
+#include "net/url_request/url_request_test_util.h"
+#include "testing/gmock/include/gmock/gmock-generated-function-mockers.h"
+#include "testing/gmock/include/gmock/gmock-matchers.h"
+#include "testing/gmock/include/gmock/gmock-more-matchers.h"
+#include "testing/gmock/include/gmock/gmock-spec-builders.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using testing::IsEmpty;
+using testing::Not;
+
+namespace {
+
+const int kInterestsRetrieverURLFetcherID = 0;
+const char kEmptyResponse[] = "{\n"
+      "\"interest\": []\n"
+    "}\n";
+
+const char kSuccessfulResponse[] = "{\n"
+    "  \"interest\": [\n"
+    "    {\n"
+    "      \"name\": \"Google\",\n"
+    "      \"imageUrl\": \"https://fake.com/fake.png\",\n"
+    "      \"relevance\": 0.9\n"
+    "    },\n"
+    "    {\n"
+    "      \"name\": \"Google Chrome\",\n"
+    "      \"imageUrl\": \"https://fake.com/fake.png\",\n"
+    "      \"relevance\": 0.98\n"
+    "    }\n"
+    "  ]\n"
+    "}\n";
+
+std::vector<InterestsRetriever::Interest> kExpectedEmptyResponse() {

[Marc Treib, 2015/09/03 13:54:55]

s/k/Get/g, also below

[tache, 2015/09/03 15:21:52]

Done.

+  return std::vector<InterestsRetriever::Interest>();
+}
+
+std::vector<InterestsRetriever::Interest> kExpectedSuccessfulResponse() {
+  std::vector<InterestsRetriever::Interest> res;
+  res.push_back(
+      InterestsRetriever::Interest{"Google", "https://fake.com/fake.png", 0.9});
+  res.push_back(InterestsRetriever::Interest{
+      "Google Chrome", "https://fake.com/fake.png", 0.98});
+  return res;
+}
+
+}  // namespace
+
+class InterestsRetrieverTest : public testing::Test {
+ public:
+  InterestsRetrieverTest()
+      : request_context_(new net::TestURLRequestContextGetter(
+            base::ThreadTaskRunnerHandle::Get())),
+        url_fetcher_factory_(new net::TestURLFetcherFactory()) {}
+
+  MOCK_METHOD1(OnReceivedInterests,
+               void(std::vector<InterestsRetriever::Interest>));
+
+ protected:
+  void GetInterests() {

[Marc Treib, 2015/09/03 13:54:55]

RequestInterests? "Get" sounds like it would return something.

[tache, 2015/09/03 15:21:53]

Done.

+    request_ = scoped_ptr<InterestsRetriever>(new InterestsRetriever(

[Marc Treib, 2015/09/03 13:54:55]

request_.reset(new ...
is shorter :)

[tache, 2015/09/03 15:21:53]

thx :D

+        request_context_.get(),
+        "secret token",
+        base::Bind(&InterestsRetrieverTest::OnReceivedInterests,
+                   base::Unretained(this)),
+        url_fetcher_factory_.get()));
+  }
+
+  net::TestURLFetcher* GetURLFetcher() {
+    net::TestURLFetcher* url_fetcher = url_fetcher_factory_->GetFetcherByID(
+        kInterestsRetrieverURLFetcherID);
+    EXPECT_TRUE(url_fetcher);
+    return url_fetcher;
+  }
+
+
+  void SendResponse(net::Error error, const std::string& response) {
+    net::TestURLFetcher* url_fetcher = GetURLFetcher();
+    url_fetcher->set_status(net::URLRequestStatus::FromError(error));
+    url_fetcher->set_response_code(net::HTTP_OK);
+    url_fetcher->SetResponseString(response);
+    url_fetcher->delegate()->OnURLFetchComplete(url_fetcher);
+  }
+
+
+  void SendValidResponse(const std::string& response) {
+    SendResponse(net::OK, response);
+  }
+
+
+  void SendFailedResponse() {
+    SendResponse(net::ERR_ABORTED, std::string());
+  }
+
+
+  base::MessageLoop message_loop_;
+  scoped_refptr<net::TestURLRequestContextGetter> request_context_;
+  scoped_ptr<net::TestURLFetcherFactory> url_fetcher_factory_;
+  scoped_ptr<InterestsRetriever> request_;
+};
+
+TEST_F(InterestsRetrieverTest, EmptyResponse) {
+  GetInterests();
+  EXPECT_CALL(*this, OnReceivedInterests(kExpectedEmptyResponse()));
+  SendValidResponse(kEmptyResponse);
+}
+
+TEST_F(InterestsRetrieverTest, SuccessfullResponse) {
+  GetInterests();
+  EXPECT_CALL(*this, OnReceivedInterests(kExpectedSuccessfulResponse()));
+  SendValidResponse(kSuccessfulResponse);
+}
+
+TEST_F(InterestsRetrieverTest, FailedResponse) {
+  GetInterests();
+  EXPECT_CALL(*this, OnReceivedInterests(kExpectedEmptyResponse()));
+  SendFailedResponse();
+}
+
+TEST_F(InterestsRetrieverTest, DefaultFakeResponse) {
+  GetInterests();
+  EXPECT_CALL(*this, OnReceivedInterests(Not(IsEmpty())));
+  SendValidResponse(InterestsRetriever::GetFakeResponseForTest());
+}