From 38ee5f310302e3d05b240c4d55e1bb4e1bd5f8e7 Mon Sep 17 00:00:00 2001
From: Salman Ahmed <email@iisalman.me>
Date: Thu, 9 Apr 2020 22:57:54 +0300
Subject: [PATCH] Add tests covering most cases of interval list checking

---
 osu.Game.Tests/Lists/IntervalListTest.cs | 141 +++++++++++++++++++++++
 1 file changed, 141 insertions(+)
 create mode 100644 osu.Game.Tests/Lists/IntervalListTest.cs

diff --git a/osu.Game.Tests/Lists/IntervalListTest.cs b/osu.Game.Tests/Lists/IntervalListTest.cs
new file mode 100644
index 0000000000..1bc1483e15
--- /dev/null
+++ b/osu.Game.Tests/Lists/IntervalListTest.cs
@@ -0,0 +1,141 @@
+// 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 NUnit.Framework;
+using osu.Game.Lists;
+
+namespace osu.Game.Tests.Lists
+{
+    [TestFixture]
+    public class IntervalListTest
+    {
+        // this is intended to be unordered to test adding intervals in unordered way.
+        private static readonly (double, double)[] test_intervals =
+        {
+            (-9.1d, -8.3d),
+            (-3.4d, 2.1d),
+            (50.0d, 9.0d), // intentionally reversing interval.
+            (5.25d, 10.50d),
+        };
+
+        [Test]
+        public void TestCheckValueInsideSingleInterval()
+        {
+            var list = new IntervalList<double> { { 1.0d, 2.0d } };
+
+            Assert.IsTrue(list.IsInAnyInterval(1.0d));
+            Assert.IsTrue(list.IsInAnyInterval(1.5d));
+            Assert.IsTrue(list.IsInAnyInterval(2.0d));
+        }
+
+        [Test]
+        public void TestCheckValuesInsideIntervals()
+        {
+            var list = new IntervalList<double>();
+
+            foreach (var (start, end) in test_intervals)
+                list.Add(start, end);
+
+            Assert.IsTrue(list.IsInAnyInterval(-8.75d));
+            Assert.IsTrue(list.IsInAnyInterval(1.0d));
+            Assert.IsTrue(list.IsInAnyInterval(7.89d));
+            Assert.IsTrue(list.IsInAnyInterval(9.8d));
+            Assert.IsTrue(list.IsInAnyInterval(15.83d));
+        }
+
+        [Test]
+        public void TestCheckValuesInRandomOrder()
+        {
+            var list = new IntervalList<double>();
+
+            foreach (var (start, end) in test_intervals)
+                list.Add(start, end);
+
+            Assert.IsTrue(list.IsInAnyInterval(9.8d));
+            Assert.IsTrue(list.IsInAnyInterval(7.89d));
+            Assert.IsTrue(list.IsInAnyInterval(1.0d));
+            Assert.IsTrue(list.IsInAnyInterval(15.83d));
+            Assert.IsTrue(list.IsInAnyInterval(-8.75d));
+        }
+
+        [Test]
+        public void TestCheckValuesOutOfIntervals()
+        {
+            var list = new IntervalList<double>();
+
+            foreach (var (start, end) in test_intervals)
+                list.Add(start, end);
+
+            Assert.IsFalse(list.IsInAnyInterval(-9.2d));
+            Assert.IsFalse(list.IsInAnyInterval(2.2d));
+            Assert.IsFalse(list.IsInAnyInterval(5.15d));
+            Assert.IsFalse(list.IsInAnyInterval(51.2d));
+        }
+
+        [Test]
+        public void TestCheckValueAfterRemovedInterval()
+        {
+            var list = new IntervalList<int> { { 50, 100 }, { 150, 200 }, { 250, 300 } };
+
+            Assert.IsTrue(list.IsInAnyInterval(75));
+            Assert.IsTrue(list.IsInAnyInterval(175));
+            Assert.IsTrue(list.IsInAnyInterval(275));
+
+            list.Remove(list[1]);
+
+            Assert.IsFalse(list.IsInAnyInterval(175));
+            Assert.IsTrue(list.IsInAnyInterval(75));
+            Assert.IsTrue(list.IsInAnyInterval(275));
+        }
+
+        [Test]
+        public void TestCheckValueAfterAddedInterval()
+        {
+            var list = new IntervalList<int> { { 50, 100 }, { 250, 300 } };
+
+            Assert.IsFalse(list.IsInAnyInterval(175));
+            Assert.IsTrue(list.IsInAnyInterval(75));
+            Assert.IsTrue(list.IsInAnyInterval(275));
+
+            list.Add(150, 200);
+
+            Assert.IsTrue(list.IsInAnyInterval(175));
+        }
+
+        [Test]
+        public void TestCheckIntervalIndexOnChecks()
+        {
+            var list = new TestIntervalList { { 1.0d, 2.0d }, { 3.0d, 4.0d }, { 5.0d, 6.0d }, { 7.0d, 8.0d } };
+
+            Assert.IsTrue(list.IsInAnyInterval(1.5d));
+            Assert.IsTrue(list.NearestIntervalIndex == 0);
+
+            Assert.IsTrue(list.IsInAnyInterval(5.5d));
+            Assert.IsTrue(list.NearestIntervalIndex == 2);
+
+            Assert.IsTrue(list.IsInAnyInterval(7.5d));
+            Assert.IsTrue(list.NearestIntervalIndex == 3);
+        }
+
+        [Test]
+        public void TestCheckIntervalIndexOnOutOfIntervalsChecks()
+        {
+            var list = new TestIntervalList { { 1.0d, 2.0d }, { 3.0d, 4.0d }, { 5.0d, 6.0d }, { 7.0d, 8.0d } };
+
+            Assert.IsFalse(list.IsInAnyInterval(4.5d));
+            Assert.IsTrue(list.NearestIntervalIndex == 1 ||
+                          list.NearestIntervalIndex == 2); // 4.5 in between 3.0-4.0 and 5.0-6.0
+
+            Assert.IsFalse(list.IsInAnyInterval(9.0d));
+            Assert.IsTrue(list.NearestIntervalIndex == 3); // 9.0 goes above 7.0-8.0
+
+            Assert.IsFalse(list.IsInAnyInterval(0.0d));
+            Assert.IsTrue(list.NearestIntervalIndex == 0); // 0.0 goes below 1.0-2.0
+        }
+
+        private class TestIntervalList : IntervalList<double>
+        {
+            public new int NearestIntervalIndex => base.NearestIntervalIndex;
+        }
+    }
+}