Introduce an example integration test around HomeController (#8)

Introduce an example integration test around HomeController.

Author: ChrisJets432

Directory.Packages.props

@@ -5,6 +5,7 @@
   </PropertyGroup>
   <ItemGroup>
     <!-- Static code analysis -->
+    <PackageVersion Include="AngleSharp" Version="1.6.0" />
     <PackageVersion Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.10" />
     <PackageVersion Include="NSubstitute" Version="6.0.0" />
     <PackageVersion Include="SonarAnalyzer.CSharp" Version="10.30.0.144632" />
@@ -31,4 +32,4 @@
     <PackageVersion Include="Microsoft.Testing.Extensions.GitHubActionsReport" Version="1.0.0-alpha.26377.5" />
     <PackageVersion Include="Microsoft.Testing.Extensions.TrxReport" Version="2.3.3" />
   </ItemGroup>
-</Project>
+</Project>

tests/SchoolAccount.IntegrationTests/Controllers/Home/HomeControllerTests.cs

@@ -0,0 +1,114 @@
+using System.Net;
+using AngleSharp;
+using AngleSharp.Dom;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.AspNetCore.TestHost;
+using NSubstitute;
+using NSubstitute.ExceptionExtensions;
+using SchoolAccount.Application.Abstractions.Messaging;
+using SchoolAccount.Application.Greetings.GetTimeSpecificHello;
+using SchoolAccount.SharedKernel;
+using Shouldly;
+
+namespace SchoolAccount.IntegrationTests.Controllers.Home;
+
+public class HomeControllerTests : IClassFixture<WebApplicationFactory<Program>>
+{
+    private readonly HttpClient _client;
+    private readonly IQueryHandler<
+        GetTimeSpecificHelloQuery,
+        GetTimeSpecificHelloResponse
+    > _getTimeSpecificHelloHandler = Substitute.For<
+        IQueryHandler<GetTimeSpecificHelloQuery, GetTimeSpecificHelloResponse>
+    >();
+
+    public HomeControllerTests(WebApplicationFactory<Program> factory)
+    {
+        _client = factory
+            .WithWebHostBuilder(builder =>
+                builder.ConfigureTestServices(services =>
+                    services.AddScoped<
+                        IQueryHandler<GetTimeSpecificHelloQuery, GetTimeSpecificHelloResponse>
+                    >(_ => _getTimeSpecificHelloHandler)
+                )
+            )
+            .CreateClient();
+    }
+
+    [Fact]
+    public async Task Ensure_that_the_home_controller_returns_a_successful_result()
+    {
+        // Arrange
+        var stubbedGetSpecificHelloResponse = new GetTimeSpecificHelloResponse(
+            GetTimeSpecificHelloHandler.Messages.Morning
+        );
+        _getTimeSpecificHelloHandler
+            .Handle(Arg.Any<GetTimeSpecificHelloQuery>(), Arg.Any<CancellationToken>())
+            .Returns(Result.Success(stubbedGetSpecificHelloResponse));
+
+        // Act
+        HttpResponseMessage response = await _client.GetAsync(
+            "/",
+            TestContext.Current.CancellationToken
+        );
+
+        // Assert
+        response.IsSuccessStatusCode.ShouldBeTrue();
+
+        string html = await response.Content.ReadAsStringAsync(
+            TestContext.Current.CancellationToken
+        );
+        IBrowsingContext context = BrowsingContext.New(Configuration.Default);
+        IDocument page = await context.OpenAsync(
+            req => req.Content(html),
+            TestContext.Current.CancellationToken
+        );
+
+        page.ShouldNotBeNull();
+
+        IElement? pageTitle = page.QuerySelector("title");
+        pageTitle.ShouldNotBeNull();
+        pageTitle.TextContent.ShouldBeEquivalentTo("Home Page");
+
+        IElement? headingElement = page.QuerySelector("h1.govuk-heading-l");
+        headingElement.ShouldNotBeNull();
+        headingElement.TextContent.ShouldBeEquivalentTo(stubbedGetSpecificHelloResponse.Message);
+
+        IElement? bodyElement = page.QuerySelector("p.govuk-body");
+        bodyElement.ShouldNotBeNull();
+        bodyElement.TextContent.ShouldContainWithoutWhitespace("In case I don't see ya");
+    }
+
+    [Fact]
+    public async Task Ensure_that_the_home_controller_returns_a_404_result_on_unknown_page()
+    {
+        // Act
+        HttpResponseMessage response = await _client.GetAsync(
+            "/orangesandapples",
+            TestContext.Current.CancellationToken
+        );
+
+        // Assert
+        response.IsSuccessStatusCode.ShouldBeFalse();
+        response.StatusCode.ShouldBe(HttpStatusCode.NotFound);
+    }
+
+    [Fact]
+    public async Task Ensure_that_when_the_home_controller_fails_it_returns_a_500_result()
+    {
+        // Arrange
+        _getTimeSpecificHelloHandler
+            .Handle(Arg.Any<GetTimeSpecificHelloQuery>(), Arg.Any<CancellationToken>())
+            .Throws(new ApplicationException("Bang!"));
+
+        // Act
+        HttpResponseMessage response = await _client.GetAsync(
+            "/",
+            TestContext.Current.CancellationToken
+        );
+
+        // Assert
+        response.IsSuccessStatusCode.ShouldBeFalse();
+        response.StatusCode.ShouldBe(HttpStatusCode.InternalServerError);
+    }
+}

tests/SchoolAccount.IntegrationTests/SchoolAccount.IntegrationTests.csproj

@@ -8,6 +8,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="AngleSharp" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" />
     <PackageReference Include="NSubstitute" />
     <PackageReference Include="Shouldly" />
@@ -20,4 +21,8 @@
   <ItemGroup>
     <Using Include="Xunit" />
   </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\SchoolAccount.Web.Mvc\SchoolAccount.Web.Mvc.csproj" />
+  </ItemGroup>
 </Project>