public void Run_ExistingEnvironmentPathIsEmptyString_PathToScriptAddedToEnvironmentPath()
        {
            CreateScript();
            fakeScriptFileName.GetScriptDirectoryReturnValue = @"d:\projects\myproject\packages\test\tools";
            fakeSession.SetEnvironmentPath(String.Empty);

            RunScript();

            string actualEnvironmentPath   = fakeSession.GetEnvironmentPath();
            string expectedEnvironmentPath = @"d:\projects\myproject\packages\test\tools";

            Assert.AreEqual(expectedEnvironmentPath, actualEnvironmentPath);
        }