Cake issue related to retrieval of relative current directory.

RetrievingCurrentDirectoryIssue.cs

using System;
using Cake.Core.IO;
using NUnit.Framework;

namespace CakeIssues
{
    [TestFixture(arguments: "./")]
    [TestFixture(arguments: @".\")]
    public class WhenRetrievingDirectory
    {
        private readonly string _directoryToRetrieve;
        private FileSystem _fileSystem;

        public WhenRetrievingDirectory(string directoryToRetrieve)
        {
            _directoryToRetrieve = directoryToRetrieve;
        }

        [SetUp]
        public void Setup()
        {
            _fileSystem = new FileSystem();
        }

        [Test]
        public void ThrowsException()
        {
            Assert.That(WhenRetrieving, Throws.Exception);
        }

        [Test]
        public void ThrowsArgumentException()
        {
            Assert.That(WhenRetrieving, Throws.ArgumentException);
        }

        [Test]
        public void ThrowsArgumentExceptionWithMessagePathIsNotOfLegalForm()
        {
            var argumentException = Assert.Throws<ArgumentException>(WhenRetrieving);

            Assert.That(argumentException.Message, Is.EqualTo("The path is not of a legal form."));
        }

        private void WhenRetrieving()
        {
            _fileSystem.GetDirectory(_directoryToRetrieve);
        }
    }
}