Added CategoryFactoryTest.

BUG=638189

Review-Url: https://codereview.chromium.org/2244123004
Cr-Commit-Position: refs/heads/master@{#412777}

components/ntp_snippets/BUILD.gn

@@ -99,6 +99,7 @@ if (is_android) {
 source_set("unit_tests") {
   testonly = true
   sources = [
+    "category_factory_unittest.cc",
     "content_suggestions_service_unittest.cc",
     "mock_content_suggestions_provider_observer.cc",
     "mock_content_suggestions_provider_observer.h",

components/ntp_snippets/category_factory_unittest.cc

+// Copyright 2016 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/ntp_snippets/category_factory.h"
+
+#include <algorithm>
+#include <vector>
+
+#include "components/ntp_snippets/category.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace ntp_snippets {
+
+class CategoryFactoryTest : public testing::Test {
+ public:
+  CategoryFactoryTest() : unused_remote_category_id_(1) {}
+
+  int GetUnusedRemoteCategoryID() { return unused_remote_category_id_++; }
+
+  bool CompareCategories(const Category& left, const Category& right) {
+    return factory()->CompareCategories(left, right);
+  }
+
+  void AddDummyRemoteCategories(int quantity) {
+    for (int i = 0; i < quantity; ++i) {
+      factory()->FromRemoteCategory(GetUnusedRemoteCategoryID());
+    }
+  }
+
+  CategoryFactory* factory() { return &factory_; }
+
+ private:
+  CategoryFactory factory_;
+  int unused_remote_category_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(CategoryFactoryTest);
+};
+
+TEST_F(CategoryFactoryTest,
+       FromKnownCategoryShouldReturnSameIdForSameCategories) {
+  const KnownCategories known_category = KnownCategories::BOOKMARKS;
+  Category first = factory()->FromKnownCategory(known_category);
+  Category second = factory()->FromKnownCategory(known_category);
+  EXPECT_EQ(first, second);
+}
+
+TEST_F(CategoryFactoryTest,
+       FromRemoteCategoryShouldReturnSameIdForSameCategories) {
+  const int remote_category_id = GetUnusedRemoteCategoryID();
+  Category first = factory()->FromRemoteCategory(remote_category_id);
+  Category second = factory()->FromRemoteCategory(remote_category_id);
+  EXPECT_EQ(first, second);
+}
+
+TEST_F(CategoryFactoryTest, FromRemoteCategoryOrder) {
+  const int small_id = GetUnusedRemoteCategoryID();
+  const int large_id = GetUnusedRemoteCategoryID();
+  // Categories are added in decreasing id order to test that they are not
+  // compared by id.
+  Category added_first = factory()->FromRemoteCategory(large_id);
+  Category added_second = factory()->FromRemoteCategory(small_id);
+  EXPECT_TRUE(CompareCategories(added_first, added_second));
+  EXPECT_FALSE(CompareCategories(added_second, added_first));
+}
+
+TEST_F(CategoryFactoryTest, FromIDValueReturnsSameKnownCategory) {
+  Category known_category =
+      factory()->FromKnownCategory(KnownCategories::BOOKMARKS);
+  Category known_category_by_id = factory()->FromIDValue(known_category.id());
+  EXPECT_EQ(known_category, known_category_by_id);
+}
+
+TEST_F(CategoryFactoryTest, FromIDValueReturnsSameRemoteCategory) {
+  const int remote_category_id = GetUnusedRemoteCategoryID();
+  Category remote_category = factory()->FromRemoteCategory(remote_category_id);
+  Category remote_category_by_id = factory()->FromIDValue(remote_category.id());
+  EXPECT_EQ(remote_category, remote_category_by_id);
+}
+
+TEST_F(CategoryFactoryTest, CompareCategoriesLocalBeforeRemote) {
+  const int remote_category_id = GetUnusedRemoteCategoryID();
+  Category remote_category = factory()->FromRemoteCategory(remote_category_id);
+  Category local_category =
+      factory()->FromKnownCategory(KnownCategories::BOOKMARKS);
+  EXPECT_TRUE(CompareCategories(local_category, remote_category));
+  EXPECT_FALSE(CompareCategories(remote_category, local_category));
+}
+
+TEST_F(CategoryFactoryTest, CompareCategoriesSame) {
+  const int remote_category_id = GetUnusedRemoteCategoryID();
+  Category remote_category = factory()->FromRemoteCategory(remote_category_id);
+  EXPECT_FALSE(CompareCategories(remote_category, remote_category));
+
+  Category local_category =
+      factory()->FromKnownCategory(KnownCategories::BOOKMARKS);
+  EXPECT_FALSE(CompareCategories(local_category, local_category));
+}
+
+TEST_F(CategoryFactoryTest, CompareCategoriesAfterAddingNew) {
+  AddDummyRemoteCategories(3);
+
+  Category consequtive_first =
+      factory()->FromRemoteCategory(GetUnusedRemoteCategoryID());
+  Category consequtive_second =
+      factory()->FromRemoteCategory(GetUnusedRemoteCategoryID());
+
+  AddDummyRemoteCategories(3);
+
+  Category nonconsequtive_first =
+      factory()->FromRemoteCategory(GetUnusedRemoteCategoryID());
+  AddDummyRemoteCategories(3);
+  Category nonconsequtive_second =
+      factory()->FromRemoteCategory(GetUnusedRemoteCategoryID());
+
+  AddDummyRemoteCategories(3);
+
+  EXPECT_TRUE(CompareCategories(consequtive_first, consequtive_second));
+  EXPECT_FALSE(CompareCategories(consequtive_second, consequtive_first));
+
+  EXPECT_TRUE(CompareCategories(nonconsequtive_first, nonconsequtive_second));
+  EXPECT_FALSE(CompareCategories(nonconsequtive_second, nonconsequtive_first));
+}
+
+}  // namespace ntp_snippets