public void TestGetCommonRootDirectory(string[] files, string expectedDirectory)
{
var environmentPathServiceMock = new Mock <IEnvironmentPathService>();
environmentPathServiceMock
.Setup(m => m.GetDirectoryName(It.IsAny <string>()))
.Returns <string>(Path.GetDirectoryName);
var pathService = new PathService(environmentPathServiceMock.Object);
var actualDirectory = pathService.GetCommonRootDirectory(files);
Assert.Equal(expectedDirectory, actualDirectory?.Replace("\\", "/"));
}