module GrainsTests open FsUnit.Xunit open Xunit open Grains [] let ``Grains on square 1`` () = let expected: Result = Ok 1UL square 1 |> should equal expected [] let ``Grains on square 2`` () = let expected: Result = Ok 2UL square 2 |> should equal expected [] let ``Grains on square 3`` () = let expected: Result = Ok 4UL square 3 |> should equal expected [] let ``Grains on square 4`` () = let expected: Result = Ok 8UL square 4 |> should equal expected [] let ``Grains on square 16`` () = let expected: Result = Ok 32768UL square 16 |> should equal expected [] let ``Grains on square 32`` () = let expected: Result = Ok 2147483648UL square 32 |> should equal expected [] let ``Grains on square 64`` () = let expected: Result = Ok 9223372036854775808UL square 64 |> should equal expected [] let ``Square 0 is invalid`` () = let expected: Result = Error "square must be between 1 and 64" square 0 |> should equal expected [] let ``Negative square is invalid`` () = let expected: Result = Error "square must be between 1 and 64" square -1 |> should equal expected [] let ``Square greater than 64 is invalid`` () = let expected: Result = Error "square must be between 1 and 64" square 65 |> should equal expected [] let ``Returns the total number of grains on the board`` () = let expected: Result = Ok 18446744073709551615UL total |> should equal expected