Merge pull request #212 from svroonland/maybe-to-list

Add Maybe<T>.ToList()
vkhorikov · Jul 10, 2020 · 0c2a1ac · 0c2a1ac
2 parents c10e048 + 6d01cb0
commit 0c2a1ac
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diff --git a/CSharpFunctionalExtensions.Tests/MaybeTests/ExtensionsTests.cs b/CSharpFunctionalExtensions.Tests/MaybeTests/ExtensionsTests.cs
@@ -415,6 +415,28 @@ public void TryFind_dict_does_not_contains_key()
             maybe.HasValue.Should().BeFalse();
         }
 
+        [Fact]
+        public void ToList_gives_empty_list_if_null()
+        {
+            Maybe<MyClass> maybe = null;
+
+            List<MyClass> myClasses = maybe.ToList();
+
+            myClasses.Count.Should().Be(0);
+        }
+
+        [Fact]
+        public void ToList_gives_single_item_list_if_not_null()
+        {
+            var instance = new MyClass();
+            Maybe<MyClass> maybe = instance;
+
+            List<MyClass> myClasses = maybe.ToList();
+
+            myClasses.Count.Should().Be(1);
+            myClasses[0].Should().Be(instance);
+        }
+
         private static Maybe<string> GetPropertyIfExists(MyClass myClass)
         {
             return myClass.Property;

diff --git a/CSharpFunctionalExtensions/Maybe/MaybeExtensions.cs b/CSharpFunctionalExtensions/Maybe/MaybeExtensions.cs
@@ -35,6 +35,11 @@ public static Result<T, E> ToResult<T, E>(this Maybe<T> maybe, E error)
             return defaultValue;
         }
 
+        public static List<T> ToList<T>(this Maybe<T> maybe)
+        {
+            return maybe.Unwrap(value => new List<T> {value}, new List<T>());
+        }
+
         public static Maybe<T> Where<T>(this Maybe<T> maybe, Func<T, bool> predicate)
         {
             if (maybe.HasNoValue)