[Payment Request] Country selection coordinator

ios/chrome/browser/ui/payments/country_selection_coordinator_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/chrome/browser/ui/payments/country_selection_coordinator.h"
+
+#include "base/mac/foundation_util.h"
+#include "base/memory/ptr_util.h"
+#include "base/test/ios/wait_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+
+class PaymentRequestCountrySelectionCoordinatorTest : public PlatformTest {};
+
+// Tests that invoking start and stop on the coordinator presents and dismisses
+// the payment request picker view controller, respectively.
+TEST_F(PaymentRequestCountrySelectionCoordinatorTest, StartAndStop) {
+  UIViewController* base_view_controller = [[UIViewController alloc] init];
+  UINavigationController* navigation_controller =
+      [[UINavigationController alloc]
+          initWithRootViewController:base_view_controller];
+
+  CountrySelectionCoordinator* coordinator =
+      [[CountrySelectionCoordinator alloc]
+          initWithBaseViewController:base_view_controller];
+
+  EXPECT_EQ(1u, navigation_controller.viewControllers.count);
+
+  [coordinator start];
+  // Short delay to allow animation to complete.
+  base::test::ios::SpinRunLoopWithMaxDelay(base::TimeDelta::FromSecondsD(1.0));
+  EXPECT_EQ(2u, navigation_controller.viewControllers.count);
+
+  [coordinator stop];
+  // Short delay to allow animation to complete.
+  base::test::ios::SpinRunLoopWithMaxDelay(base::TimeDelta::FromSecondsD(1.0));
+  EXPECT_EQ(1u, navigation_controller.viewControllers.count);
+}