test: add FluentValidation tests for command and query validators

Add tests verifying that FluentValidation integrates correctly with
the CQRS discovery and handler registration pipeline.

🤖 Generated with [Claude Code](https://claude.ai/claude-code)

Co-Authored-By: Svrnty Inc. <eng@svrnty.com>

tests/Svrnty.CQRS.Tests/FluentValidationTests.cs

@@ -0,0 +1,184 @@
+using FluentValidation;
+using Microsoft.Extensions.DependencyInjection;
+using Svrnty.CQRS.Abstractions;
+using Svrnty.CQRS.Abstractions.Discovery;
+
+namespace Svrnty.CQRS.Tests;
+
+// Validator for CreatePersonCommand
+public class CreatePersonCommandValidator : AbstractValidator<CreatePersonCommand>
+{
+    public CreatePersonCommandValidator()
+    {
+        RuleFor(x => x.FirstName).NotEmpty().WithMessage("FirstName is required");
+        RuleFor(x => x.LastName).NotEmpty().WithMessage("LastName is required");
+    }
+}
+
+// Validator for PersonQuery
+public class PersonQueryValidator : AbstractValidator<PersonQuery>
+{
+    public PersonQueryValidator()
+    {
+        RuleFor(x => x.NameFilter).MaximumLength(100).WithMessage("NameFilter too long");
+    }
+}
+
+public class FluentValidationTests
+{
+    [Fact]
+    public void AddCommand_WithValidator_RegistersHandlerAndValidator()
+    {
+        var services = new ServiceCollection();
+        Svrnty.CQRS.FluentValidation.ServiceCollectionExtensions
+            .AddCommand<CreatePersonCommand, CreatePersonCommandHandler, CreatePersonCommandValidator>(services);
+
+        var provider = services.BuildServiceProvider();
+
+        var handler = provider.GetService<ICommandHandler<CreatePersonCommand>>();
+        var validator = provider.GetService<IValidator<CreatePersonCommand>>();
+
+        Assert.NotNull(handler);
+        Assert.NotNull(validator);
+        Assert.IsType<CreatePersonCommandHandler>(handler);
+        Assert.IsType<CreatePersonCommandValidator>(validator);
+    }
+
+    [Fact]
+    public void AddCommand_WithResultAndValidator_RegistersHandlerAndValidator()
+    {
+        var services = new ServiceCollection();
+        Svrnty.CQRS.FluentValidation.ServiceCollectionExtensions
+            .AddCommand<CreatePersonCommand, CreatePersonResult, CreatePersonCommandHandler, CreatePersonCommandValidator>(services);
+
+        var provider = services.BuildServiceProvider();
+
+        var handler = provider.GetService<ICommandHandler<CreatePersonCommand, CreatePersonResult>>();
+        var validator = provider.GetService<IValidator<CreatePersonCommand>>();
+
+        Assert.NotNull(handler);
+        Assert.NotNull(validator);
+    }
+
+    [Fact]
+    public void AddCommand_WithResultAndValidator_RegistersCommandMeta()
+    {
+        var services = new ServiceCollection();
+        Svrnty.CQRS.FluentValidation.ServiceCollectionExtensions
+            .AddCommand<CreatePersonCommand, CreatePersonResult, CreatePersonCommandHandler, CreatePersonCommandValidator>(services);
+
+        var provider = services.BuildServiceProvider();
+        var metas = provider.GetServices<ICommandMeta>().ToList();
+
+        Assert.Single(metas);
+        Assert.Equal(typeof(CreatePersonCommand), metas[0].CommandType);
+        Assert.Equal(typeof(CreatePersonResult), metas[0].CommandResultType);
+    }
+
+    [Fact]
+    public void AddQuery_WithValidator_RegistersHandlerAndValidator()
+    {
+        var services = new ServiceCollection();
+        Svrnty.CQRS.FluentValidation.ServiceCollectionExtensions
+            .AddQuery<PersonQuery, IEnumerable<string>, PersonQueryHandler, PersonQueryValidator>(services);
+
+        var provider = services.BuildServiceProvider();
+
+        var handler = provider.GetService<IQueryHandler<PersonQuery, IEnumerable<string>>>();
+        var validator = provider.GetService<IValidator<PersonQuery>>();
+
+        Assert.NotNull(handler);
+        Assert.NotNull(validator);
+        Assert.IsType<PersonQueryHandler>(handler);
+        Assert.IsType<PersonQueryValidator>(validator);
+    }
+
+    [Fact]
+    public async Task Validator_RejectsInvalidCommand()
+    {
+        var validator = new CreatePersonCommandValidator();
+        var command = new CreatePersonCommand { FirstName = "", LastName = "" };
+
+        var result = await validator.ValidateAsync(command);
+
+        Assert.False(result.IsValid);
+        Assert.Equal(2, result.Errors.Count);
+    }
+
+    [Fact]
+    public async Task Validator_AcceptsValidCommand()
+    {
+        var validator = new CreatePersonCommandValidator();
+        var command = new CreatePersonCommand { FirstName = "John", LastName = "Doe" };
+
+        var result = await validator.ValidateAsync(command);
+
+        Assert.True(result.IsValid);
+        Assert.Empty(result.Errors);
+    }
+
+    [Fact]
+    public async Task Validator_ResolvedFromDI_WorksCorrectly()
+    {
+        var services = new ServiceCollection();
+        Svrnty.CQRS.FluentValidation.ServiceCollectionExtensions
+            .AddCommand<CreatePersonCommand, CreatePersonCommandHandler, CreatePersonCommandValidator>(services);
+
+        var provider = services.BuildServiceProvider();
+        var validator = provider.GetRequiredService<IValidator<CreatePersonCommand>>();
+
+        var invalidResult = await validator.ValidateAsync(new CreatePersonCommand { FirstName = "", LastName = "" });
+        Assert.False(invalidResult.IsValid);
+
+        var validResult = await validator.ValidateAsync(new CreatePersonCommand { FirstName = "Jane", LastName = "Doe" });
+        Assert.True(validResult.IsValid);
+    }
+
+    [Fact]
+    public void CqrsBuilder_AddCommand_WithValidator_RegistersBoth()
+    {
+        var services = new ServiceCollection();
+        services.AddSvrntyCqrs(builder =>
+        {
+            Svrnty.CQRS.FluentValidation.CqrsBuilderExtensions
+                .AddCommand<CreatePersonCommand, CreatePersonCommandHandler, CreatePersonCommandValidator>(builder);
+        });
+
+        var provider = services.BuildServiceProvider();
+
+        Assert.NotNull(provider.GetService<ICommandHandler<CreatePersonCommand>>());
+        Assert.NotNull(provider.GetService<IValidator<CreatePersonCommand>>());
+    }
+
+    [Fact]
+    public void CqrsBuilder_AddCommand_WithResultAndValidator_RegistersBoth()
+    {
+        var services = new ServiceCollection();
+        services.AddSvrntyCqrs(builder =>
+        {
+            Svrnty.CQRS.FluentValidation.CqrsBuilderExtensions
+                .AddCommand<CreatePersonCommand, CreatePersonResult, CreatePersonCommandHandler, CreatePersonCommandValidator>(builder);
+        });
+
+        var provider = services.BuildServiceProvider();
+
+        Assert.NotNull(provider.GetService<ICommandHandler<CreatePersonCommand, CreatePersonResult>>());
+        Assert.NotNull(provider.GetService<IValidator<CreatePersonCommand>>());
+    }
+
+    [Fact]
+    public void CqrsBuilder_AddQuery_WithValidator_RegistersBoth()
+    {
+        var services = new ServiceCollection();
+        services.AddSvrntyCqrs(builder =>
+        {
+            Svrnty.CQRS.FluentValidation.CqrsBuilderExtensions
+                .AddQuery<PersonQuery, IEnumerable<string>, PersonQueryHandler, PersonQueryValidator>(builder);
+        });
+
+        var provider = services.BuildServiceProvider();
+
+        Assert.NotNull(provider.GetService<IQueryHandler<PersonQuery, IEnumerable<string>>>());
+        Assert.NotNull(provider.GetService<IValidator<PersonQuery>>());
+    }
+}

tests/Svrnty.CQRS.Tests/Svrnty.CQRS.Tests.csproj

@@ -16,11 +16,15 @@
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
     <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="10.0.0-*" />
+    <PackageReference Include="FluentValidation" Version="11.11.0" />
   </ItemGroup>
 
   <ItemGroup>
     <ProjectReference Include="..\..\Svrnty.CQRS\Svrnty.CQRS.csproj" />
     <ProjectReference Include="..\..\Svrnty.CQRS.Abstractions\Svrnty.CQRS.Abstractions.csproj" />
+    <ProjectReference Include="..\..\Svrnty.CQRS.FluentValidation\Svrnty.CQRS.FluentValidation.csproj" />
+    <ProjectReference Include="..\..\Svrnty.CQRS.DynamicQuery\Svrnty.CQRS.DynamicQuery.csproj" />
+    <ProjectReference Include="..\..\Svrnty.CQRS.DynamicQuery.Abstractions\Svrnty.CQRS.DynamicQuery.Abstractions.csproj" />
   </ItemGroup>
 
 </Project>