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));
}