Autofixture example

SqlOnly/Blog.Tests.Integration/Blog.Tests.Integration.csproj

@@ -9,6 +9,9 @@
 	<ItemGroup>
 		<PackageReference Include="Accelergreat.EntityFramework.SqlServer" Version="1.3.6" />
 		<PackageReference Include="Accelergreat.Xunit" Version="1.3.6" />
+		<PackageReference Include="AutoFixture" Version="4.18.0" />
+		<PackageReference Include="AutoFixture.AutoNSubstitute" Version="4.18.0" />
+		<PackageReference Include="AutoFixture.Xunit2" Version="4.18.0" />
 		<PackageReference Include="FluentAssertions" Version="6.7.0" />
 	</ItemGroup>
 

SqlOnly/Blog.Tests.Integration/Customisation/AutoNSubstitudeDataAttribute.cs

@@ -0,0 +1,27 @@
+using AutoFixture;
+using AutoFixture.AutoNSubstitute;
+using AutoFixture.Xunit2;
+
+namespace Blog.Tests.Integration.Customisation;
+
+public class AutoNSubstituteDataAttribute : AutoDataAttribute
+{
+    public AutoNSubstituteDataAttribute(params Type[] optionalCustomizationTypes)
+        : base(() => BuildFixture(optionalCustomizationTypes))
+    {
+    }
+
+    // ReSharper disable once ParameterTypeCanBeEnumerable.Local
+    private static IFixture BuildFixture(Type[] optionalCustomizationTypes)
+    {
+        var fixture = new Fixture()
+            .Customize(new AutoNSubstituteCustomization());
+
+        foreach (var customizationType in optionalCustomizationTypes)
+        {
+            fixture.Customize((ICustomization)Activator.CreateInstance(customizationType));
+        }
+
+        return fixture;
+    }
+}

SqlOnly/Blog.Tests.Integration/Extensions/ReflectionExtensions.cs

@@ -0,0 +1,25 @@
+#nullable enable
+using System.Reflection;
+
+namespace Blog.Tests.Integration.Extensions;
+
+public static class ReflectionExtensions
+{
+    public static T SetThroughReflection<T>(this T entity, string propertyName, object? value)
+    {
+        var properties = typeof(T).GetProperties(BindingFlags.FlattenHierarchy |
+                                                 BindingFlags.Instance |
+                                                 BindingFlags.Public).ToArray();
+
+        var named = properties.Where(x => x.Name == propertyName).ToArray();
+
+        var property = typeof(T).GetProperties(BindingFlags.FlattenHierarchy |
+                                               BindingFlags.Instance |
+                                               BindingFlags.Public)
+            .Single(s => s.SetMethod != null && s.Name == propertyName);
+
+        property.SetValue(entity, value);
+
+        return entity;
+    }
+}

SqlOnly/Blog.Tests.Integration/Services/BlogServiceTests.cs

@@ -3,6 +3,8 @@
 using Blog.Data;
 using Blog.Data.Entities;
 using Blog.Services;
+using Blog.Tests.Integration.Customisation;
+using Blog.Tests.Integration.Extensions;
 using FluentAssertions;
 using Microsoft.EntityFrameworkCore;
 using Xunit;
@@ -29,11 +31,11 @@ public async Task Inserts_a_Post()
     {
         var title = "A test post";
         var text = "This post was made in an integration test and was saved to a SQL instance managed by Accelergreat.";
-        
+
         var user = GetComponent<BlogSqlAccelergreatComponent>().Users.First();
 
         await using var testContext = CreateContext();
-        
+
         var service = new BlogService(testContext);
 
         var resultingPost = await service.CreatePost(user.UserId, title, text);
@@ -80,4 +82,33 @@ public async Task Inserts_a_Comment()
         databasePost.PostId.Should().Be(post.PostId);
         databasePost.Text.Should().Be(text);
     }
+
+    [Theory, AutoNSubstituteData]
+    public async Task Inserts_a_Post_from__AutoFixture(Post post)
+    {
+        var user = GetComponent<BlogSqlAccelergreatComponent>().Users.First();
+
+        post.SetThroughReflection(nameof(Post.UserId), user.UserId);
+
+        await using var testContext = CreateContext();
+
+        var service = new BlogService(testContext);
+
+        var resultingPost = await service.CreatePost(post);
+
+        // Assert the result from the service is as expected
+        resultingPost.UserId.Should().Be(user.UserId);
+        resultingPost.Title.Should().Be(post.Title);
+        resultingPost.Text.Should().Be(post.Text);
+
+        // Assert the data stored to the database is as expected
+        // This is done on a separate DbContext to ensure in-memory instances are not used
+        await using var assertionContext = CreateContext();
+        var databasePost = await assertionContext.Set<Post>().SingleAsync(x => x.PostId == resultingPost.PostId);
+
+        databasePost.UserId.Should().Be(user.UserId);
+        databasePost.Title.Should().Be(post.Title);
+        databasePost.Text.Should().Be(post.Text);
+    }
+
 }

SqlOnly/Blog/Services/BlogService.cs

@@ -16,6 +16,11 @@ public async Task<Post> CreatePost(int userId, string title, string text)
     {
         var post = new Post(userId, title, text);
 
+        return await CreatePost(post);
+    }
+
+    public async Task<Post> CreatePost(Post post)
+    {
         _dbContext.Set<Post>().Add(post);
 
         await _dbContext.SaveChangesAsync();