module DominoesTests open FsUnit.Xunit open Xunit open Dominoes [] let ``Empty input = empty output`` () = let dominoes = [] canChain dominoes |> should equal true [] let ``Singleton input = singleton output`` () = let dominoes = [(1, 1)] canChain dominoes |> should equal true [] let ``Singleton that can't be chained`` () = let dominoes = [(1, 2)] canChain dominoes |> should equal false [] let ``Three elements`` () = let dominoes = [(1, 2); (3, 1); (2, 3)] canChain dominoes |> should equal true [] let ``Can reverse dominoes`` () = let dominoes = [(1, 2); (1, 3); (2, 3)] canChain dominoes |> should equal true [] let ``Can't be chained`` () = let dominoes = [(1, 2); (4, 1); (2, 3)] canChain dominoes |> should equal false [] let ``Disconnected - simple`` () = let dominoes = [(1, 1); (2, 2)] canChain dominoes |> should equal false [] let ``Disconnected - double loop`` () = let dominoes = [(1, 2); (2, 1); (3, 4); (4, 3)] canChain dominoes |> should equal false [] let ``Disconnected - single isolated`` () = let dominoes = [(1, 2); (2, 3); (3, 1); (4, 4)] canChain dominoes |> should equal false [] let ``Need backtrack`` () = let dominoes = [(1, 2); (2, 3); (3, 1); (2, 4); (2, 4)] canChain dominoes |> should equal true [] let ``Separate loops`` () = let dominoes = [(1, 2); (2, 3); (3, 1); (1, 1); (2, 2); (3, 3)] canChain dominoes |> should equal true [] let ``Nine elements`` () = let dominoes = [(1, 2); (5, 3); (3, 1); (1, 2); (2, 4); (1, 6); (2, 3); (3, 4); (5, 6)] canChain dominoes |> should equal true [] let ``Separate three-domino loops`` () = let dominoes = [(1, 2); (2, 3); (3, 1); (4, 5); (5, 6); (6, 4)] canChain dominoes |> should equal false