From 0c0b5b2f84c9a440b95827181aa38a912c38ce99 Mon Sep 17 00:00:00 2001
From: Mahmoud Ali <muddibr@gmail.com>
Date: Thu, 26 Sep 2019 13:49:14 -0300
Subject: [PATCH] Provide tests for ConfirmNavigation exception scenarios

---
 .../PageNavigationServiceFixture.cs           | 63 +++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/Source/Xamarin/Prism.Forms.Tests/Navigation/PageNavigationServiceFixture.cs b/Source/Xamarin/Prism.Forms.Tests/Navigation/PageNavigationServiceFixture.cs
index 4724d8a6c..9add26d94 100644
--- a/Source/Xamarin/Prism.Forms.Tests/Navigation/PageNavigationServiceFixture.cs
+++ b/Source/Xamarin/Prism.Forms.Tests/Navigation/PageNavigationServiceFixture.cs
@@ -411,6 +411,69 @@ public async void Navigate_ToContentPage_ViewModelHasIConfirmNavigation_False()
             Assert.True(viewModel.OnConfirmNavigationCalled);
             Assert.True(rootPage.Navigation.ModalStack.Count == 0);
         }
+        
+        [Fact]
+        public async void GoBack_ViewModelWithIConfirmNavigationFalse_ResultException()
+        {
+            var navigationService = new PageNavigationServiceMock(_container, _applicationProvider, _loggerFacade);
+            var rootPage = new ContentPage() {BindingContext = new ContentPageMockViewModel()};
+            ((IPageAware) navigationService).Page = rootPage;
+
+            var viewModel = rootPage.BindingContext as ContentPageMockViewModel;
+
+            var navParams = new NavigationParameters();
+            navParams.Add("canNavigate", false);
+
+            var navigationResult = await navigationService.GoBackAsync(navParams);
+
+            Assert.True(viewModel.OnConfirmNavigationCalled);
+            Assert.NotNull(navigationResult.Exception);
+            Assert.IsType<NavigationException>(navigationResult.Exception);
+            Assert.False(navigationResult.Success);
+            Assert.Equal(NavigationException.IConfirmNavigationReturnedFalse, navigationResult.Exception.Message);
+        }
+        
+        [Fact]
+        public async void GoBackToRoot_ViewModelWithIConfirmNavigationFalse_ResultException()
+        {
+            var navigationService = new PageNavigationServiceMock(_container, _applicationProvider, _loggerFacade);
+            var rootPage = new ContentPage() {BindingContext = new ContentPageMockViewModel()};
+            ((IPageAware) navigationService).Page = rootPage;
+
+            var viewModel = rootPage.BindingContext as ContentPageMockViewModel;
+
+            var navParams = new NavigationParameters();
+            navParams.Add("canNavigate", false);
+
+            var navigationResult = await navigationService.GoBackToRootAsync(navParams);
+
+            Assert.True(viewModel.OnConfirmNavigationCalled);
+            Assert.NotNull(navigationResult.Exception);
+            Assert.IsType<NavigationException>(navigationResult.Exception);
+            Assert.False(navigationResult.Success);
+            Assert.Equal(NavigationException.IConfirmNavigationReturnedFalse, navigationResult.Exception.Message);
+        }
+        
+        [Fact]
+        public async void NavigateAsync_ViewModelWithIConfirmNavigationFalse_ResultException()
+        {
+            var navigationService = new PageNavigationServiceMock(_container, _applicationProvider, _loggerFacade);
+            var rootPage = new ContentPage() {BindingContext = new ContentPageMockViewModel()};
+            ((IPageAware) navigationService).Page = rootPage;
+
+            var viewModel = rootPage.BindingContext as ContentPageMockViewModel;
+
+            var navParams = new NavigationParameters();
+            navParams.Add("canNavigate", false);
+
+            var navigationResult = await navigationService.NavigateAsync("ContentPage", navParams);
+
+            Assert.True(viewModel.OnConfirmNavigationCalled);
+            Assert.NotNull(navigationResult.Exception);
+            Assert.IsType<NavigationException>(navigationResult.Exception);
+            Assert.False(navigationResult.Success);
+            Assert.Equal(NavigationException.IConfirmNavigationReturnedFalse, navigationResult.Exception.Message);
+        }
 
         [Fact]
         public async void Navigate_ToNavigatonPage_ViewModelHasINavigationAware()