Introduce BrowserList and Browser classes for iOS.

ios/clean/chrome/browser/model/browser_list_unittest.mm

+// Copyright 2017 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.
+
+#import "ios/clean/chrome/browser/model/browser_list.h"
+
+#include <memory>
+
+#include "base/macros.h"
+#include "ios/chrome/browser/browser_state/test_chrome_browser_state.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+class BrowserListTest : public PlatformTest {
+ public:
+  BrowserListTest() {
+    browser_state_ = TestChromeBrowserState::Builder().Build();
+  }
+
+  ios::ChromeBrowserState* browser_state() { return browser_state_.get(); }
+
+ private:
+  std::unique_ptr<ios::ChromeBrowserState> browser_state_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserListTest);
+};
+
+TEST_F(BrowserListTest, Initialisation) {
+  EXPECT_TRUE(BrowserList::FromBrowserState(browser_state()));
+}
+
+TEST_F(BrowserListTest, CreateBrowser) {
+  BrowserList* browser_list = BrowserList::FromBrowserState(browser_state());
+  EXPECT_EQ(0, browser_list->GetBrowserCount());
+
+  Browser* browser = browser_list->CreateNewBrowser();
+  ASSERT_EQ(1, browser_list->GetBrowserCount());
+  EXPECT_EQ(browser, browser_list->GetBrowserAtIndex(0));
+}
+
+TEST_F(BrowserListTest, CloseBrowser) {
+  BrowserList* browser_list = BrowserList::FromBrowserState(browser_state());
+  browser_list->CreateNewBrowser();
+  EXPECT_EQ(1, browser_list->GetBrowserCount());
+
+  browser_list->CloseBrowserAtIndex(0);
+  EXPECT_EQ(0, browser_list->GetBrowserCount());
+}
+
+TEST_F(BrowserListTest, ContainsIndex) {
+  BrowserList* browser_list = BrowserList::FromBrowserState(browser_state());
+  EXPECT_EQ(0, browser_list->GetBrowserCount());
+  EXPECT_FALSE(browser_list->ContainsIndex(-1));
+  EXPECT_FALSE(browser_list->ContainsIndex(0));
+  EXPECT_FALSE(browser_list->ContainsIndex(1));
+
+  browser_list->CreateNewBrowser();
+  EXPECT_EQ(1, browser_list->GetBrowserCount());
+  EXPECT_FALSE(browser_list->ContainsIndex(-1));
+  EXPECT_TRUE(browser_list->ContainsIndex(0));
+  EXPECT_FALSE(browser_list->ContainsIndex(1));
+
+  browser_list->CreateNewBrowser();
+  EXPECT_EQ(2, browser_list->GetBrowserCount());
+  EXPECT_FALSE(browser_list->ContainsIndex(-1));
+  EXPECT_TRUE(browser_list->ContainsIndex(0));
+  EXPECT_TRUE(browser_list->ContainsIndex(1));
+}