public void CheckForDuplicatedVersion()
        {
            var versions = new long[] { 1, 2, 3, 4, 2, 4 };

            var ex = Assert.Throws <DuplicatedVersionException>(() =>
                                                                MigrationAssembly.CheckForDuplicatedVersion(versions));

            Assert.AreEqual(2, ex.Versions.Count);
            Assert.That(ex.Versions.Contains(2));
            Assert.That(ex.Versions.Contains(4));
        }