public void TestCreateFromInvalidEnumerable()
{
// create a chain
var fakeHeaders = new FakeHeaders();
var header0 = fakeHeaders.GenesisChained();
var header1 = fakeHeaders.NextChained();
// create builder from out of order enumerable
AssertMethods.AssertThrows<InvalidOperationException>(() => new ChainBuilder(new[] { header1, header0 }));
}