Add query handler tests

.gitignore

@@ -5,3 +5,4 @@ riderModule.iml
 /_ReSharper.Caches/
 .idea
 .vs
+CleanArchitecture.sln.DotSettings.user

CleanArchitecture.Application.Tests/CleanArchitecture.Application.Tests.csproj

@@ -9,7 +9,9 @@
     </PropertyGroup>
 
     <ItemGroup>
+        <PackageReference Include="FluentAssertions" Version="6.10.0" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.2" />
+        <PackageReference Include="MockQueryable.Moq" Version="7.0.0" />
         <PackageReference Include="Moq" Version="4.18.4" />
         <PackageReference Include="xunit" Version="2.4.2" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">

CleanArchitecture.Application.Tests/Fixtures/Queries/Users/GetAllUsersTestFixture.cs

@@ -1,5 +1,7 @@
 using CleanArchitecture.Application.Queries.Users.GetAll;
+using CleanArchitecture.Domain.Entities;
 using CleanArchitecture.Domain.Interfaces.Repositories;
+using MockQueryable.Moq;
 using Moq;
 
 namespace CleanArchitecture.Application.Tests.Fixtures.Queries.Users;
@@ -8,11 +10,30 @@ public sealed class GetAllUsersTestFixture : QueryHandlerBaseFixture
 {
     public Mock<IUserRepository> UserRepository { get; }
     public GetAllUsersQueryHandler Handler { get; }
+    public Guid ExistingUserId { get; } = Guid.NewGuid();
 
     public GetAllUsersTestFixture()
     {
         UserRepository = new();
 
+        SetupUserRepositoryGetAllAsync();
+        
         Handler = new(UserRepository.Object);
     }
+    
+    private void SetupUserRepositoryGetAllAsync()
+    {
+        var user = new Mock<User>(() =>
+                new User(
+                    ExistingUserId, 
+                    "max@mustermann.com", 
+                    "Max", 
+                    "Mustermann"));
+
+        var query = new[] { user.Object }.AsQueryable().BuildMock();
+        
+        UserRepository
+            .Setup(x => x.GetAllNoTracking())
+            .Returns(query);
+    }
 }

CleanArchitecture.Application.Tests/Fixtures/Queries/Users/GetUserByIdTestFixture.cs

@@ -1,7 +1,7 @@
-using CleanArchitecture.Application.Queries.Users.GetAll;
 using CleanArchitecture.Application.Queries.Users.GetUserById;
-using CleanArchitecture.Domain.Interfaces;
+using CleanArchitecture.Domain.Entities;
 using CleanArchitecture.Domain.Interfaces.Repositories;
+using MockQueryable.Moq;
 using Moq;
 
 namespace CleanArchitecture.Application.Tests.Fixtures.Queries.Users;
@@ -10,11 +10,30 @@ public sealed class GetUserByIdTestFixture : QueryHandlerBaseFixture
 {
     public Mock<IUserRepository> UserRepository { get; }
     public GetUserByIdQueryHandler Handler { get; }
+    public Guid ExistingUserId { get; } = Guid.NewGuid();
 
     public GetUserByIdTestFixture()
     {
         UserRepository = new();
         
+        SetupUserRepositoryGetAllAsync();
+        
         Handler = new(UserRepository.Object, Bus.Object);
     }
+    
+    private void SetupUserRepositoryGetAllAsync()
+    {
+        var user = new Mock<User>(() =>
+            new User(
+                ExistingUserId, 
+                "max@mustermann.com", 
+                "Max", 
+                "Mustermann"));
+
+        var query = new[] { user.Object }.AsQueryable().BuildMock();
+        
+        UserRepository
+            .Setup(x => x.GetAllNoTracking())
+            .Returns(query);
+    }
 }

CleanArchitecture.Application.Tests/Queries/Users/GetAllUsersQueryHandlerTests.cs

@@ -1,6 +1,24 @@
+using CleanArchitecture.Application.Tests.Fixtures.Queries.Users;
+using FluentAssertions;
+using Xunit;
+
 namespace CleanArchitecture.Application.Tests.Queries.Users;
 
 public sealed class GetAllUsersQueryHandlerTests
 {
+    private readonly GetAllUsersTestFixture _fixture = new();
 
+    [Fact]
+    public async Task Should_Get_All_Users()
+    {
+        var result = await _fixture.Handler.Handle(
+            new(),
+            default);
+        
+        _fixture.VerifyNoDomainNotification();
+
+        result.Should().NotBeNull();
+        result.Should().ContainSingle();
+        result.FirstOrDefault().Id.Should().Be(_fixture.ExistingUserId);
+    }
 }

CleanArchitecture.Application.Tests/Queries/Users/GetUserByIdQueryHandlerTests.cs

@@ -1,6 +1,41 @@
+using CleanArchitecture.Application.Queries.Users.GetUserById;
+using CleanArchitecture.Application.Tests.Fixtures.Queries.Users;
+using CleanArchitecture.Domain.Errors;
+using FluentAssertions;
+using Xunit;
+
 namespace CleanArchitecture.Application.Tests.Queries.Users;
 
 public sealed class GetUserByIdQueryHandlerTests
 {
+    private readonly GetUserByIdTestFixture _fixture = new();
 
+    [Fact]
+    public async Task Should_Get_Existing_User()
+    {
+        var result = await _fixture.Handler.Handle(
+            new(_fixture.ExistingUserId),
+            default);
+        
+        _fixture.VerifyNoDomainNotification();
+
+        result.Should().NotBeNull();
+        result!.Id.Should().Be(_fixture.ExistingUserId);
+    }
+    
+    [Fact]
+    public async Task Should_Raise_Notification_For_No_User()
+    {
+        var request = new GetUserByIdQuery(Guid.NewGuid());
+        var result = await _fixture.Handler.Handle(
+            request,
+            default);
+        
+        _fixture.VerifyExistingNotification(
+            nameof(GetUserByIdQuery),
+            ErrorCodes.ObjectNotFound,
+            $"User with id {request.UserId} could not be found");
+
+        result.Should().BeNull();
+    }
 }

CleanArchitecture.Application/Queries/Users/GetUserById/GetUserByIdQueryHandler.cs

@@ -26,8 +26,7 @@ public sealed class GetUserByIdQueryHandler :
     {
         var user = _userRepository
             .GetAllNoTracking()
-            .Where(x => x.Id == request.UserId)
+            .FirstOrDefault(x => x.Id == request.UserId);
-            .FirstOrDefault();
 
         if (user == null)
         {