#115 - Adding placeholders for default services

docs/samples/tests/xunit/MockHttpClientBunitHelpers.cs

@@ -0,0 +1,47 @@
+namespace Bunit.Docs.Samples
+{
+    using Bunit;
+    using Microsoft.Extensions.DependencyInjection;
+    using RichardSzalay.MockHttp;
+    using System;
+    using System.Net;
+    using System.Net.Http;
+    using System.Net.Http.Headers;
+    using System.Text.Json;
+
+    public static class MockHttpClientBunitHelpers
+	{
+		public static MockHttpMessageHandler AddMockHttpClient(this TestServiceProvider services)
+		{
+			var mockHttpHandler = new MockHttpMessageHandler();
+			var httpClient = mockHttpHandler.ToHttpClient();
+			httpClient.BaseAddress = new Uri("http://localhost");
+			services.AddSingleton<HttpClient>(httpClient);
+			return mockHttpHandler;
+		}
+
+		public static MockedRequest RespondJson<T>(this MockedRequest request, T content)
+		{
+			request.Respond(req =>
+			{
+				var response = new HttpResponseMessage(HttpStatusCode.OK);
+				response.Content = new StringContent(JsonSerializer.Serialize(content));
+				response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
+				return response;
+			});
+			return request;
+		}
+
+		public static MockedRequest RespondJson<T>(this MockedRequest request, Func<T> contentProvider)
+		{
+			request.Respond(req =>
+			{
+				var response = new HttpResponseMessage(HttpStatusCode.OK);
+				response.Content = new StringContent(JsonSerializer.Serialize(contentProvider()));
+				response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
+				return response;
+			});
+			return request;
+		}
+	}
+}

docs/samples/tests/xunit/bunit.docs.xunit.samples.csproj

@@ -5,6 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="RichardSzalay.MockHttp" Version="6.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.6.1" />
     <PackageReference Include="xunit" Version="2.4.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.4.1">

docs/site/docs/test-doubles/mocking-httpclient.md

@@ -5,4 +5,32 @@ title: Mocking HttpClient
 
 # Mocking `HttpClient`
 
-TODO - https://github.com/egil/bunit/issues/61
+Mocking the `HttpClient` service in .NET Core is a bit more clumbersome than interface-based services like `IJSRuntime`. 
+There is currently no built-in mock for `HttpClient` in bUnit, but with the use of 
+[RichardSzalay.MockHttp](https://www.nuget.org/packages/RichardSzalay.MockHttp/) we can easily add one that works
+with bUnit.
+
+To use RichardSzalay.MockHttp, add the following package reference to your test project's .csproj file:
+
+```xml
+<PackageReference Include="RichardSzalay.MockHttp" Version="6.0.0" />
+```
+
+To make it easier to work with [RichardSzalay.MockHttp](https://www.nuget.org/packages/RichardSzalay.MockHttp/), add 
+the following extension class to your test project. It makes it easier to add the `HttpClient` mock to 
+bUnit's test context's `Services` collection, and configure responses to requests:
+
+[!code-csharp[MockHttpClientBunitHelpers.cs](../../../samples/tests/xunit/MockHttpClientBunitHelpers.cs?start=3&end=46)]
+
+With the helper methods in place, you can do the following in your tests:
+
+```csharp
+using var ctx = new TestContext();
+var mock = ctx.Services.AddMockHttpClient();
+mock.When("/getData").RespondJson(new List<Data>{ ... });
+```
+
+This registers the mock `HttpClient` in bUnit's test context's `Services` collection, and then tells the mock that when a request is received for `/getData`, it should respond with the `new List<Data>{ ... }`, serialized as JSON.
+
+> [!TIP]
+> You can add addtional `RespondXXX` methods to the `MockHttpClientBunitHelpers` class to fit your testing needs.

docs/site/docs/toc.md

@@ -23,6 +23,7 @@
 
 # [Test Doubles](xref:test-doubles)
 ## [Faking Authorization](xref:faking-auth)
+## [Mocking HttpClient](xref:mocking-httpclient)
 ## [Mocking IJSRuntime](xref:mocking-ijsruntime)
 
 # [Miscellaneous testing tips](xref:misc-test-tips)

src/bunit.web/Extensions/TestServiceProviderExtensions.cs

@@ -1,10 +1,16 @@
+using System.Net.Http;
 using Bunit.Diffing;
 using Bunit.Rendering;
 using Bunit.TestDoubles.Authorization;
+using Bunit.TestDoubles.HttpClient;
 using Bunit.TestDoubles.JSInterop;
+using Bunit.TestDoubles.Localization;
+using Bunit.TestDoubles.NavigationManagement;
 using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Components;
 using Microsoft.AspNetCore.Components.Authorization;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Localization;
 using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Logging.Abstractions;
 using Microsoft.JSInterop;
@@ -25,6 +31,9 @@ public static IServiceCollection AddDefaultTestContextServices(this IServiceColl
 			services.AddSingleton<AuthenticationStateProvider, PlaceholderAuthenticationStateProvider>();
 			services.AddSingleton<IAuthorizationService, PlaceholderAuthorizationService>();
 			services.AddSingleton<IJSRuntime, PlaceholderJSRuntime>();
+			services.AddSingleton<NavigationManager, PlaceholderNavigationManager>();
+			services.AddSingleton<HttpClient, PlaceholderHttpClient>();
+			services.AddSingleton<IStringLocalizer, PlaceholderStringLocalization>();
 			services.AddSingleton<HtmlComparer>();
 			services.AddSingleton<BunitHtmlParser>();
 			services.AddSingleton<IRenderedComponentActivator, RenderedComponentActivator>();

src/bunit.web/TestDoubles/HttpClient/MissingMockHttpClientException.cs

@@ -0,0 +1,29 @@
+using System;
+using System.Net.Http;
+
+namespace Bunit.TestDoubles.HttpClient
+{
+	/// <summary>
+	/// Exception use to indicate that a mock HttpClient is required by a test
+	/// but was not provided.
+	/// </summary>
+	public sealed class MissingMockHttpClientException : Exception
+	{
+		/// <summary>
+		/// The request that was sent via the http client
+		/// </summary>
+		public HttpRequestMessage Request { get; }
+
+		/// <summary>
+		/// Creates a new instance of the <see cref="MissingMockHttpClientException"/>
+		/// with the request that would have been handled
+		/// </summary>
+		/// <param name="request">The request being handled by the client</param>
+		public MissingMockHttpClientException(HttpRequestMessage request)
+			: base($"This test requires a HttpClient to be supplied, because the component under test invokes the HttpClient during the test. The request that was sent is contained within the '{nameof(Request)}' attribute of this exception. Guidance on mocking the HttpClient is available on bUnit's website.")
+		{
+			Request = request;
+			HelpLink = "https://bunit.egilhansen.com/docs/test-doubles/mocking-httpclient";
+		}
+	}
+}

src/bunit.web/TestDoubles/HttpClient/PlaceholderHttpClient.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Bunit.TestDoubles.HttpClient
+{
+	public class PlaceholderHttpClient : System.Net.Http.HttpClient
+	{
+		/// <summary>
+		/// Creates an instance of <see cref="PlaceholderHttpClient"/>
+		/// with a <see cref="PlaceholderHttpMessageHandler"/> message handler
+		/// </summary>
+		[System.Diagnostics.CodeAnalysis.SuppressMessage("Reliability", "CA2000:Dispose objects before losing scope", Justification = "<Pending>")]
+		public PlaceholderHttpClient()
+			: base(new PlaceholderHttpMessageHandler())
+		{
+			BaseAddress = new Uri("http://localhost");
+		}
+
+		/// <summary>
+		/// This MessageHandler for HttpClient is used to provide users with helpful
+		/// exceptions if they fail to provide a mock when required.
+		/// </summary>
+		private class PlaceholderHttpMessageHandler : HttpMessageHandler
+		{
+			/// <summary>
+			///
+			/// </summary>
+			/// <param name="request"></param>
+			/// <param name="cancellationToken"></param>
+			/// <returns></returns>
+			/// <exception cref="MissingMockHttpClientException"></exception>
+			protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+			{
+				throw new MissingMockHttpClientException(request);
+			}
+		}
+	}
+}

src/bunit.web/TestDoubles/HttpClient/PlaceholderHttpMessageHandler.cs

@@ -0,0 +1,8 @@
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Bunit.TestDoubles.HttpClient
+{
+
+}

src/bunit.web/TestDoubles/JSInterop/MissingMockJSRuntimeException.cs

@@ -26,11 +26,11 @@ public class MissingMockJSRuntimeException : Exception
 		/// <param name="identifier">The identifer used in the invocation.</param>
 		/// <param name="arguments">The args used in the invocation, if any</param>
 		public MissingMockJSRuntimeException(string identifier, object?[]? arguments)
-			: base($"This test requires a IJSRuntime to be supplied, because the component under test invokes the IJSRuntime during the test. The invoked method is '{identifier}' and the invocation arguments are stored in the {nameof(Arguments)} property of this exception. Guidance on mocking the IJSRuntime is available in the testing library's Wiki.")
+			: base($"This test requires a IJSRuntime to be supplied, because the component under test invokes the IJSRuntime during the test. The invoked method is '{identifier}' and the invocation arguments are stored in the {nameof(Arguments)} property of this exception. Guidance on mocking the IJSRuntime is available on bUnit's website.")
 		{
 			Identifier = identifier;
 			Arguments = arguments ?? Array.Empty<object?>();
-			HelpLink = "https://github.com/egil/razor-components-testing-library/wiki/Mocking-JsRuntime";
+			HelpLink = "https://bunit.egilhansen.com/docs/test-doubles/mocking-ijsruntime";
 		}
 	}
 }

src/bunit.web/TestDoubles/JSInterop/MockJSRuntimeInvokeHandler.cs

@@ -21,7 +21,7 @@ public class MockJSRuntimeInvokeHandler
 		public IReadOnlyDictionary<string, List<JSRuntimeInvocation>> Invocations => _invocations;
 
 		/// <summary>
-		/// Gets whether the mock is running in <see cref="JSRuntimeMockMode.Loose"/> or 
+		/// Gets whether the mock is running in <see cref="JSRuntimeMockMode.Loose"/> or
 		/// <see cref="JSRuntimeMockMode.Strict"/>.
 		/// </summary>
 		public JSRuntimeMockMode Mode { get; }
@@ -50,7 +50,7 @@ public IJSRuntime ToJSRuntime()
 		/// </summary>
 		/// <typeparam name="TResult">The result type of the invocation</typeparam>
 		/// <param name="identifier">The identifier to setup a response for</param>
-		/// <param name="argumentsMatcher">A matcher that is passed arguments received in invocations to <paramref name="identifier"/>. If it returns true the invocation is matched.</param>
+		/// <param name="argumentsMatcher">A matcher that is passed arguments received in invocTestServiceProviderExtensions.cs ations to <paramref name="identifier"/>. If it returns true the invocation is matched.</param>
 		/// <returns>A <see cref="JSRuntimePlannedInvocation{TResult}"/>.</returns>
 		public JSRuntimePlannedInvocation<TResult> Setup<TResult>(string identifier, Func<IReadOnlyList<object?>, bool> argumentsMatcher)
 		{
@@ -90,7 +90,7 @@ public JSRuntimePlannedInvocation SetupVoid(string identifier, Func<IReadOnlyLis
 		}
 
 		/// <summary>
-		/// Configure a planned JSInterop invocation with the <paramref name="identifier"/> 
+		/// Configure a planned JSInterop invocation with the <paramref name="identifier"/>
 		/// and <paramref name="arguments"/>, that should not receive any result.
 		/// </summary>
 		/// <param name="identifier">The identifier to setup a response for</param>

src/bunit.web/TestDoubles/Localization/MissingMockStringLocalizationException.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+
+namespace Bunit.TestDoubles.Localization
+{
+	/// <summary>
+	/// Exception use to indicate that a IStringLocalizer is required by a test
+	/// but was not provided.
+	/// </summary>
+	public class MissingMockStringLocalizationException : Exception
+	{
+
+		/// <summary>
+		/// The arguments that were passed into the localizer
+		/// </summary>
+		public IReadOnlyList<object?> Arguments { get; }
+
+		/// <summary>
+		/// Creates a new instance of the <see cref="MissingMockStringLocalizationException"/>
+		/// with the method name and arguments used in the invocation
+		/// </summary>
+		/// <param name="methodName">The method that was called on the localizer</param>
+		/// <param name="arguments">The arguments that were passed in</param>
+		public MissingMockStringLocalizationException(string methodName, params object?[]? arguments)
+			:base($"This test requires a IStringLocalizer to be supplied, because the component under test invokes the IStringLocalizer during the test. The method that was called was '{methodName}', the parameters are container within the '{nameof(Arguments)}' property of this exception.")
+		{
+			Arguments = arguments ?? Array.Empty<object?>();;
+		}
+	}
+}

src/bunit.web/TestDoubles/Localization/PlaceholderStringLocalization.cs

@@ -0,0 +1,48 @@
+using System.Globalization;
+using System.Collections.Generic;
+using Microsoft.Extensions.Localization;
+
+namespace Bunit.TestDoubles.Localization
+{
+	/// <summary>
+	/// This IStringLocalizer is used to provide users with helpful exceptions if they fail to provide a mock when required.
+	/// </summary>
+	internal class PlaceholderStringLocalization : IStringLocalizer
+	{
+		/// <summary>
+		/// Will throw exception to prompt the user
+		/// </summary>
+		/// <param name="includeParentCultures"></param>
+		/// <returns></returns>
+		/// <exception cref="MissingMockStringLocalizationException"></exception>
+		public IEnumerable<LocalizedString> GetAllStrings(bool includeParentCultures)
+			=> throw new MissingMockStringLocalizationException(nameof(GetAllStrings), includeParentCultures);
+
+		/// <summary>
+		/// Will throw exception to prompt the user
+		/// </summary>
+		/// <param name="culture"></param>
+		/// <returns></returns>
+		/// <exception cref="MissingMockStringLocalizationException"></exception>
+		public IStringLocalizer WithCulture(CultureInfo culture)
+			=> throw new MissingMockStringLocalizationException(nameof(WithCulture), culture);
+
+		/// <summary>
+		/// Will throw exception to prompt the user
+		/// </summary>
+		/// <param name="name"></param>
+		public LocalizedString this[string name]
+			=> Throw(name);
+
+		/// <summary>
+		/// Will throw exception to prompt the user
+		/// </summary>
+		/// <param name="name"></param>
+		/// <param name="arguments"></param>
+		public LocalizedString this[string name, params object[] arguments]
+			=> Throw(name, arguments);
+
+		private static LocalizedString Throw(string name, params object?[]? args)
+			=> throw new MissingMockStringLocalizationException("GetByIndex", name, args);
+	}
+}

src/bunit.web/TestDoubles/NavigationManagement/MissingMockNavigationManagerException.cs

@@ -0,0 +1,38 @@
+using System;
+
+namespace Bunit.TestDoubles.NavigationManagement
+{
+	/// <summary>
+	/// Exception use to indicate that a NavigationManager is required by a test
+	/// but was not provided.
+	/// </summary>
+	public class MissingMockNavigationManagerException : Exception
+	{
+		private static string ExceptionMessage(string url, bool forceLoad) =>
+			$"This test requires a NavigationManager to be supplied, because the component under test invokes the NavigationManager during the test. The url that was requested was '{url}' with a force reload value of '{forceLoad.ToString()}'.";
+
+		/// <summary>
+		/// Creates a new instance of the <see cref="MissingMockNavigationManagerException"/>
+		/// with the arguments used in the invocation.
+		/// </summary>
+		/// <param name="url">Uri to navigate to</param>
+		/// <param name="forceLoad">Whether to force load</param>
+		public MissingMockNavigationManagerException(string url, bool forceLoad)
+			: base (ExceptionMessage(url, forceLoad))
+		{
+
+		}
+
+		/// <summary>
+		/// Creates a new instance of the <see cref="MissingMockNavigationManagerException"/>
+		/// with the arguments used in the invocation.
+		/// </summary>
+		/// <param name="url">Uri to navigate to</param>
+		/// <param name="forceLoad">Whether to force load</param>
+		public MissingMockNavigationManagerException(Uri url, bool forceLoad)
+			: base (ExceptionMessage(url?.ToString() ?? string.Empty, forceLoad))
+		{
+
+		}
+	}
+}

src/bunit.web/TestDoubles/NavigationManagement/PlaceholderNavigationManager.cs

@@ -0,0 +1,30 @@
+using Microsoft.AspNetCore.Components;
+
+namespace Bunit.TestDoubles.NavigationManagement
+{
+	/// <summary>
+	/// This NavigationManager is used to provide users with helpful exceptions if they fail to provide a mock when required.
+	/// </summary>
+	internal class PlaceholderNavigationManager : NavigationManager
+	{
+		/// <summary>
+		/// Will throw exception to prompt user
+		/// </summary>
+		/// <param name="uri"></param>
+		/// <param name="forceLoad"></param>
+		/// <exception cref="MissingMockNavigationManagerException"></exception>
+		protected override void NavigateToCore(string uri, bool forceLoad)
+		{
+			throw new MissingMockNavigationManagerException(uri, forceLoad);
+		}
+
+		/// <summary>
+		/// Will initialize the navigation manager with a hard coded
+		/// value of http://localhost:5000/
+		/// </summary>
+		protected override void EnsureInitialized()
+		{
+			Initialize("http://localhost/", "http://localhost/");
+		}
+	}
+}