Add tests showing expected behaviour of naming helper

osu.Game.Tests/Utils/NamingUtilsTest.cs

@@ -0,0 +1,132 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Linq;
+using NUnit.Framework;
+using osu.Game.Utils;
+
+namespace osu.Game.Tests.Utils
+{
+    [TestFixture]
+    public class NamingUtilsTest
+    {
+        [Test]
+        public void TestEmptySet()
+        {
+            string nextBestName = NamingUtils.GetNextBestName(Enumerable.Empty<string>(), "New Difficulty");
+
+            Assert.AreEqual("New Difficulty", nextBestName);
+        }
+
+        [Test]
+        public void TestNotTaken()
+        {
+            string[] existingNames =
+            {
+                "Something",
+                "Entirely",
+                "Different"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty", nextBestName);
+        }
+
+        [Test]
+        public void TestNotTakenButClose()
+        {
+            string[] existingNames =
+            {
+                "New Difficulty(1)",
+                "New Difficulty (abcd)",
+                "New Difficulty but not really"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty", nextBestName);
+        }
+
+        [Test]
+        public void TestAlreadyTaken()
+        {
+            string[] existingNames =
+            {
+                "New Difficulty"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty (1)", nextBestName);
+        }
+
+        [Test]
+        public void TestAlreadyTakenWithDifferentCase()
+        {
+            string[] existingNames =
+            {
+                "new difficulty"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty (1)", nextBestName);
+        }
+
+        [Test]
+        public void TestAlreadyTakenWithBrackets()
+        {
+            string[] existingNames =
+            {
+                "new difficulty (copy)"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty (copy)");
+
+            Assert.AreEqual("New Difficulty (copy) (1)", nextBestName);
+        }
+
+        [Test]
+        public void TestMultipleAlreadyTaken()
+        {
+            string[] existingNames =
+            {
+                "New Difficulty",
+                "New difficulty (1)",
+                "new Difficulty (2)",
+                "New DIFFICULTY (3)"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty (4)", nextBestName);
+        }
+
+        [Test]
+        public void TestEvenMoreAlreadyTaken()
+        {
+            string[] existingNames = Enumerable.Range(1, 30).Select(i => $"New Difficulty ({i})").Append("New Difficulty").ToArray();
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty (31)", nextBestName);
+        }
+
+        [Test]
+        public void TestMultipleAlreadyTakenWithGaps()
+        {
+            string[] existingNames =
+            {
+                "New Difficulty",
+                "New Difficulty (1)",
+                "New Difficulty (4)",
+                "New Difficulty (9)"
+            };
+
+            string nextBestName = NamingUtils.GetNextBestName(existingNames, "New Difficulty");
+
+            Assert.AreEqual("New Difficulty (2)", nextBestName);
+        }
+    }
+}

osu.Game/Utils/NamingUtils.cs

@@ -0,0 +1,15 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+
+namespace osu.Game.Utils
+{
+    public static class NamingUtils
+    {
+        public static string GetNextBestName(IEnumerable<string> existingNames, string desiredName)
+        {
+            return null;
+        }
+    }
+}