Merge pull request #781 from polyadic/implement-list-extensions

Implements FindIndexOrNone and FindLastIndexOrNone on List
polyadic · Feb 27, 2024 · 6bfe87a · 6bfe87a
2 parents f1c3169 + 870497c
commit 6bfe87a
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diff --git a/Funcky.Test/Extensions/ListExtensionsTest.cs b/Funcky.Test/Extensions/ListExtensionsTest.cs
@@ -18,4 +18,24 @@ public void GivenAListIndexOfOrNoneReturnsSomeIndexIfTheElementIsInTheList()
 
         FunctionalAssert.Some(2, list.IndexOfOrNone("Epsilon"));
     }
+
+    [Fact]
+    public void GivenAListAndAPredicateFindIndexOrNoneReturnsTheFirstElementMatchingThePredicateInTheGivenInterval()
+    {
+        List<string> list = ["Alpha", "Gamma", "Alien", "Epsilon"];
+
+        FunctionalAssert.Some(0, list.FindIndexOrNone(item => item.StartsWith("Al")));
+        FunctionalAssert.Some(2, list.FindIndexOrNone(2, item => item.StartsWith("Al")));
+        FunctionalAssert.None(list.FindIndexOrNone(3, 1, item => item.StartsWith("Al")));
+    }
+
+    [Fact]
+    public void GivenAListAndAPredicateFindLastIndexOrNoneReturnsTheLastElementMatchingThePredicateInTheGivenInterval()
+    {
+        List<string> list = ["Alpha", "Gamma", "Alien", "Epsilon"];
+
+        FunctionalAssert.Some(2, list.FindLastIndexOrNone(item => item.StartsWith("Al")));
+        FunctionalAssert.Some(0, list.FindLastIndexOrNone(1, item => item.StartsWith("Al")));
+        FunctionalAssert.None(list.FindLastIndexOrNone(3, 1, item => item.StartsWith("Al")));
+    }
 }
diff --git a/Funcky/Extensions/ListExtensions.cs b/Funcky/Extensions/ListExtensions.cs
@@ -7,4 +7,28 @@ public static class ListExtensions
     [Pure]
     public static Option<int> IndexOfOrNone<TValue>(this IList<TValue> list, TValue value)
         => MapNotFoundToNone(list.IndexOf(value));
+
+    [Pure]
+    public static Option<int> FindIndexOrNone<TValue>(this List<TValue> list, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindIndex(match));
+
+    [Pure]
+    public static Option<int> FindIndexOrNone<TValue>(this List<TValue> list, int startIndex, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindIndex(startIndex, match));
+
+    [Pure]
+    public static Option<int> FindIndexOrNone<TValue>(this List<TValue> list, int startIndex, int count, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindIndex(startIndex, count, match));
+
+    [Pure]
+    public static Option<int> FindLastIndexOrNone<TValue>(this List<TValue> list, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindLastIndex(match));
+
+    [Pure]
+    public static Option<int> FindLastIndexOrNone<TValue>(this List<TValue> list, int startIndex, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindLastIndex(startIndex, match));
+
+    [Pure]
+    public static Option<int> FindLastIndexOrNone<TValue>(this List<TValue> list, int startIndex, int count, Predicate<TValue> match)
+        => MapNotFoundToNone(list.FindLastIndex(startIndex, count, match));
 }
diff --git a/Funcky/PublicAPI.Unshipped.txt b/Funcky/PublicAPI.Unshipped.txt
@@ -12,6 +12,12 @@ Funcky.Monads.Result<TValidResult>.OrElse(System.Func<System.Exception!, Funcky.
 Funcky.UpCast<TResult>
 static Funcky.Extensions.EnumerableExtensions.InspectEmpty<TSource>(this System.Collections.Generic.IEnumerable<TSource>! source, System.Action! inspector) -> System.Collections.Generic.IEnumerable<TSource>!
 static Funcky.Extensions.EnumeratorExtensions.MoveNextOrNone<T>(this System.Collections.Generic.IEnumerator<T>! enumerator) -> Funcky.Monads.Option<T>
+static Funcky.Extensions.ListExtensions.FindIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, int startIndex, int count, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
+static Funcky.Extensions.ListExtensions.FindIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, int startIndex, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
+static Funcky.Extensions.ListExtensions.FindIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
+static Funcky.Extensions.ListExtensions.FindLastIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, int startIndex, int count, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
+static Funcky.Extensions.ListExtensions.FindLastIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, int startIndex, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
+static Funcky.Extensions.ListExtensions.FindLastIndexOrNone<TValue>(this System.Collections.Generic.List<TValue>! list, System.Predicate<TValue>! match) -> Funcky.Monads.Option<int>
 static Funcky.Extensions.ParseExtensions.ParseByteOrNone(this System.ReadOnlySpan<byte> candidate, System.Globalization.NumberStyles style, System.IFormatProvider? provider) -> Funcky.Monads.Option<byte>
 static Funcky.Extensions.ParseExtensions.ParseByteOrNone(this System.ReadOnlySpan<byte> candidate, System.IFormatProvider? provider) -> Funcky.Monads.Option<byte>
 static Funcky.Extensions.ParseExtensions.ParseByteOrNone(this System.ReadOnlySpan<byte> candidate) -> Funcky.Monads.Option<byte>