Imports System Imports Xunit Public Class GrainsTests Public Sub Grains_on_square_1() Assert.Equal(1UL, Square(1)) End Sub Public Sub Grains_on_square_2() Assert.Equal(2UL, Square(2)) End Sub Public Sub Grains_on_square_3() Assert.Equal(4UL, Square(3)) End Sub Public Sub Grains_on_square_4() Assert.Equal(8UL, Square(4)) End Sub Public Sub Grains_on_square_16() Assert.Equal(32768UL, Square(16)) End Sub Public Sub Grains_on_square_32() Assert.Equal(2147483648UL, Square(32)) End Sub Public Sub Grains_on_square_64() Assert.Equal(9223372036854775808UL, Square(64)) End Sub Public Sub Square_0_raises_an_exception() Assert.Throws(Of ArgumentOutOfRangeException)(Function() Square(0)) End Sub Public Sub Negative_square_raises_an_exception() Assert.Throws(Of ArgumentOutOfRangeException)(Function() Square(-1)) End Sub Public Sub Square_greater_than_64_raises_an_exception() Assert.Throws(Of ArgumentOutOfRangeException)(Function() Square(65)) End Sub Public Sub Returns_the_total_number_of_grains_on_the_board() Assert.Equal(18446744073709551615UL, Total()) End Sub End Class