Upstream Chrome on iOS source code [4/11].

ios/chrome/browser/ui/browser_container_view_unittest.mm

+// 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.
+
+#import "ios/chrome/browser/ui/browser_container_view.h"
+
+#import "base/mac/scoped_nsobject.h"
+#include "testing/platform_test.h"
+
+// Fixture for BrowserContainerView testing.
+class BrowserContainerViewTest : public PlatformTest {
+ protected:
+  void SetUp() override {
+    PlatformTest::SetUp();
+
+    browser_container_view_.reset([[BrowserContainerView alloc] init]);
+    ASSERT_TRUE(browser_container_view_);
+    content_view_.reset([[UIView alloc] init]);
+    ASSERT_TRUE(content_view_);
+  }
+  base::scoped_nsobject<BrowserContainerView> browser_container_view_;
+  base::scoped_nsobject<UIView> content_view_;
+};
+
+// Tests adding a new content view when BrowserContainerView does not currently
+// have a content view.
+TEST_F(BrowserContainerViewTest, AddingContentView) {
+  ASSERT_FALSE([content_view_ superview]);
+
+  [browser_container_view_ displayContentView:content_view_];
+  EXPECT_EQ(static_cast<UIView*>(browser_container_view_),
+            [content_view_ superview]);
+}
+
+// Tests removing previously added content view.
+TEST_F(BrowserContainerViewTest, RemovingContentView) {
+  [browser_container_view_ displayContentView:content_view_];
+  ASSERT_EQ(static_cast<UIView*>(browser_container_view_),
+            [content_view_ superview]);
+
+  [browser_container_view_ displayContentView:nil];
+  EXPECT_FALSE([content_view_ superview]);
+}
+
+// Tests adding a new content view when BrowserContainerView already has a
+// content view.
+TEST_F(BrowserContainerViewTest, ReplacingContentView) {
+  [browser_container_view_ displayContentView:content_view_];
+  ASSERT_EQ(static_cast<UIView*>(browser_container_view_),
+            [content_view_ superview]);
+
+  base::scoped_nsobject<UIView> content_view2([[UIView alloc] init]);
+  [browser_container_view_ displayContentView:content_view2];
+  EXPECT_FALSE([content_view_ superview]);
+  EXPECT_EQ(static_cast<UIView*>(browser_container_view_),
+            [content_view2 superview]);
+}