result/src/Result.Tests/ExtensionsEnumerableTests.cs

namespace Geekeey.Extensions.Result.Tests;

[TestFixture]
internal sealed class ExtensionsEnumerableTests
{
	[Test]
	public void Join_ReturnsAllSuccess_ForSequenceContainingAllSuccess()
	{
		IEnumerable<Result<int>> xs = [1, 2, 3, 4, 5];

		var result = xs.Join();

		Assert.Multiple(() =>
		{
			Assert.That(result.IsSuccess, Is.True);
			Assert.That(result.Value, Is.EquivalentTo(new[] { 1, 2, 3, 4, 5 }));
		});
	}

	[Test]
	public void Join_ReturnsFirstFailure_ForSequenceContainingFailure()
	{
		IEnumerable<Result<int>> xs =
		[
			Success(1),
			Success(2),
			Failure<int>("error 1"),
			Success(4),
			Failure<int>("error 2")
		];

		var result = xs.Join();

		Assert.Multiple(() =>
		{
			Assert.That(result.IsSuccess, Is.False);
			Assert.That(result.Error?.Message, Is.EqualTo("error 1"));
		});
	}

	[Test]
	public void Join_ReturnsSuccess_ForEmptySequence()
	{
		IEnumerable<Result<int>> xs = [];

		var result = xs.Join();

		Assert.Multiple(() =>
		{
			Assert.That(result.IsSuccess, Is.True);
			Assert.That(result.Value, Is.Empty);
		});
	}
}