DiamondTests.cs

using System;
using System.Linq;
using FsCheck;
using FsCheck.NUnit;

namespace DiamondGenerator.Tests
{
	[NUnit.Framework.TestFixture]
	public class DiamondTests
	{
		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property NotEmpty(char c)
		{
			return Diamond.Generate(c)
				.All(s => s != string.Empty)
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property FirstLineContainsA(char c)
		{
			return Diamond.Generate(c)
				.First().Contains('A')
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property LastLineContainsA(char c)
		{
			return Diamond.Generate(c)
				.Last().Contains('A')
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property DiamondWidthEqualsHeight(char c)
		{
			var diamond = Diamond.Generate(c).ToList();
			return diamond
				.All(row => row.Length == diamond.Count())
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property SymmetricAroundVerticalAxis(char c)
		{
			return Diamond.Generate(c)
				.All(row => row.SequenceEqual(row.Reverse()))
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property SymmetricAroundHorizontalAxis(char c)
		{
			var diamond = Diamond.Generate(c).ToArray();
			return diamond.SequenceEqual(diamond.Reverse())
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property ThereIsSingleLineContainsInputLetter(char c)
		{
			_ = Diamond.Generate(c).Single(row => row.Contains(c));
			return true.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property InputLetterRowContainsNoPaddingSpaces(char c)
		{
			return Diamond.Generate(c)
				.Any(row => row.Contains(c) && row == row.Trim())
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property EachLineContainsNoMoreTwoLetters(char c)
		{
			return Diamond.Generate(c)
				.All(row => row.Count(char.IsLetter) <= 2)
				.ToProperty();
		}

		[Property(Arbitrary = new[] {typeof(LetterGenerator)})]
		public Property FirstHalfLinesIsOrderedByAlphabetic(char c)
		{
			var diamond = Diamond.Generate(c).ToList();
			return diamond
				.Take(diamond.Count() / 2)
				.Select(row => row.First(char.IsLetter))
				.SequenceEqual(Enumerable.Range('A', c).Select(Convert.ToChar))
				.ToProperty();
		}
	}
}