Hack p4merge into approval tests

gistfile1.cs

    [SetUpFixture]
    public class HackToSetupApprovalTestsToFindP4Merge
    {
        [SetUp]
        public void SetUpFixture()
        {
            var field = typeof(FirstWorkingReporter).GetField("reporters", BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.FlattenHierarchy);
            var currentItems = (IEnumerable<IEnvironmentAwareReporter>)field.GetValue(DiffReporter.INSTANCE);

            var newitems = new[] { P4MergeDiffReporter.INSTANCE }.Concat(currentItems).ToArray();

            field.SetValue(DiffReporter.INSTANCE, newitems);
        }
    }

    public class P4MergeDiffReporter : GenericDiffReporter
    {
        private static readonly string PATH = DotNet4Utilities.GetPathInProgramFilesX86("Perforce\\p4merge.exe");
        public static readonly P4MergeDiffReporter INSTANCE = new P4MergeDiffReporter();

        public P4MergeDiffReporter()
            : base(PATH, "Could not find P4Merge at {0}, please install it".FormatWith(new object[] { PATH }))
        {
        }
    }