public void GetEdgesShouldIncludeAllCombinations() { var tile = new Tile { Image = new[] { "1234", "ABCD", "6789", "ZYXW" } }; var edges = _day20.GetEdgesForTile(tile); var expected = new[] { "1234", "Z6A1", //rot 90 "WXYZ", //rot 90 "4D9W", //rot 90 "4321", //flip "W9D4", //rot 90 "ZYXW", //rot 90 "1A6Z", //rot 90 }; CollectionAssert.AreEquivalent(expected, edges); }