Musify/backend/Tests/Musify.Application.Tests/Users/CreateUserCommandHandlerTests.cs

using ErrorOr;
using Musify.Application.Tests.TestSupport;
using Musify.Application.Users;
using Xunit;

namespace Musify.Application.Tests.Users;

public sealed class CreateUserCommandHandlerTests : HandlerTestBase
{
    private CreateUserCommandHandler CreateHandler() => new(Database, NoOpLogger<CreateUserCommandHandler>());

    [Fact]
    public async Task Handle_NewId_CreatesUser()
    {
        var command = new CreateUserCommand(1, "Jane Doe", "Jane", "Doe");

        var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

        Assert.False(result.IsError);
        Assert.Equal("Jane Doe", result.Value.Name);
        Assert.Equal(1, result.Value.Id);

        var stored = await Database.Users.FindAsync([1L], TestContext.Current.CancellationToken);
        Assert.NotNull(stored);
        Assert.Equal("JANE DOE", stored.NormalizedName);
    }

    [Fact]
    public async Task Handle_IdAlreadyExists_ReturnsConflict()
    {
        var existing = TestEntities.User(1);
        await SeedAsync(existing);

        var command = new CreateUserCommand(1, "Someone Else", null, null);

        var result = await CreateHandler().Handle(command, TestContext.Current.CancellationToken);

        Assert.Equal(ErrorType.Conflict, result.FirstError.Type);
    }
}