[ios] RootCoordinator and view controller.

ios/clean/chrome/browser/ui/root/root_container_view_controller_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/ui/root/root_container_view_controller.h"
+
+#import "ios/clean/chrome/browser/ui/animators/zoom_transition_delegate.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#import "third_party/ocmock/OCMock/OCMock.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace {
+
+// Tests that RootContainerViewController conforms to ZoomTransitionDelegate.
+TEST(RootContainerViewControllerTest, TestConformsToZoomTransitionDelegate) {
+  EXPECT_TRUE([RootContainerViewController
+      conformsToProtocol:@protocol(ZoomTransitionDelegate)]);
+}
+
+// Tests that calls to |rectForZoomWithKey| are forwarded to the
+// contentViewController.
+TEST(RootContainerViewControllerTest, TestForwardingMethod) {
+  id contentViewController = OCMProtocolMock(@protocol(ZoomTransitionDelegate));
+  RootContainerViewController* viewController =
+      [[RootContainerViewController alloc] init];
+  viewController.contentViewController = contentViewController;
+  [viewController rectForZoomWithKey:nil inView:nil];
+  [[contentViewController verify] rectForZoomWithKey:[OCMArg any]
+                                              inView:[OCMArg any]];
+}
+

[lpromero, 2017/04/12 08:58:49]

Could you add a test for the switching of contentViewController? Making sure the
new one is added, and the old one removed?

[edchin, 2017/04/13 07:39:15]

Done.

+}  // namespace