feat: IEnumerable<T>.ConditionalAppend(Maybe<T>)

Base.Tests/Structures/EnumerableExtensionTests.cs

@@ -20,4 +20,30 @@ public class EnumerableExtensionTests
 	[TestCase(new object[] { "hi", "there" }, false, "there", ExpectedResult = new object[] { "hi", "there" })]
 	public object[] TestConditionalWhere(object[] input, bool condition, object valueToKeep) =>
 		input.ConditionalWhere(condition, x => x.Equals(valueToKeep)).ToArray();
+
+	[Test]
+	public void TestConditionalAppendWithMaybe_HasAppendedItem_WhenMaybeHasValue()
+	{
+		var baseArray = new[] { 0, 1, 2 };
+
+		var result = baseArray
+			.ConditionalAppend(Maybe.Just(3))
+			.ToArray();
+
+		Assert.That(result, Has.Length.EqualTo(4));
+		Assert.That(result, Is.EquivalentTo(new[] { 0, 1, 2, 3 }));
+	}
+
+	[Test]
+	public void TestConditionalAppendWithMaybe_DoesNotHaveAppendedItem_WhenMaybeIsEmpty()
+	{
+		var baseArray = new[] { 0, 1, 2 };
+
+		var result = baseArray
+			.ConditionalAppend(Maybe.Empty<int>())
+			.ToArray();
+
+		Assert.That(result, Has.Length.EqualTo(3));
+		Assert.That(result, Is.EquivalentTo(new[] { 0, 1, 2 }));
+	}
 }

Base/Structures/EnumerableExtensions.cs

@@ -11,6 +11,9 @@ public static class EnumerableExtensions
 
 	public static IEnumerable<T> ConditionalAppend<T>(this IEnumerable<T> enumerable, bool condition, T second) =>
 		condition ? enumerable.Append(second) : enumerable;
+
+	public static IEnumerable<T> ConditionalAppend<T>(this IEnumerable<T> enumerable, Maybe<T> item) =>
+		item.HasValue ? enumerable.Append(item.Value) : enumerable;
 	
 	public static IEnumerable<T> ConditionalWhere<T>(this IEnumerable<T> enumerable, bool condition, Func<T, bool> pred) =>
 		!condition ? enumerable : enumerable.Where(pred);