add multi-part episode tests (#189)

ErsatzTV.Core.Tests/Scheduling/MultiPartEpisodeGrouperTests.cs

@@ -0,0 +1,100 @@
+using System.Collections.Generic;
+using ErsatzTV.Core.Domain;
+using ErsatzTV.Core.Scheduling;
+using FluentAssertions;
+using NUnit.Framework;
+
+namespace ErsatzTV.Core.Tests.Scheduling
+{
+    public class MultiPartEpisodeGrouperTests
+    {
+        [Test]
+        public void NotGrouped_Grouped_NotGrouped()
+        {
+            var mediaItems = new List<MediaItem>
+            {
+                NamedEpisode("Episode 1"),
+                NamedEpisode("Episode 2 (1)"),
+                NamedEpisode("Episode 3 (2)"),
+                NamedEpisode("Episode 4"),
+            };
+
+            List<GroupedMediaItem> result = MultiPartEpisodeGrouper.GroupMediaItems(mediaItems);
+
+            result.Count.Should().Be(3);
+            result[0].First.Should().Be(mediaItems[0]);
+            result[1].First.Should().Be(mediaItems[1]);
+            result[1].Additional[0].Should().Be(mediaItems[2]);
+            result[2].First.Should().Be(mediaItems[3]);
+        }
+
+        [Test]
+        public void Grouped_NotGrouped()
+        {
+            var mediaItems = new List<MediaItem>
+            {
+                NamedEpisode("Episode 1 (1)"),
+                NamedEpisode("Episode 2 (2)"),
+                NamedEpisode("Episode 3"),
+            };
+
+            List<GroupedMediaItem> result = MultiPartEpisodeGrouper.GroupMediaItems(mediaItems);
+
+            result.Count.Should().Be(2);
+            result[0].First.Should().Be(mediaItems[0]);
+            result[0].Additional[0].Should().Be(mediaItems[1]);
+            result[1].First.Should().Be(mediaItems[2]);
+        }
+
+        [Test]
+        public void Grouped_NotGrouped_Grouped()
+        {
+            var mediaItems = new List<MediaItem>
+            {
+                NamedEpisode("Episode 1 (1)"),
+                NamedEpisode("Episode 2 (2)"),
+                NamedEpisode("Episode 3"),
+                NamedEpisode("Episode 4 (1)"),
+                NamedEpisode("Episode 5 (2)"),
+            };
+
+            List<GroupedMediaItem> result = MultiPartEpisodeGrouper.GroupMediaItems(mediaItems);
+
+            result.Count.Should().Be(3);
+            result[0].First.Should().Be(mediaItems[0]);
+            result[0].Additional[0].Should().Be(mediaItems[1]);
+            result[1].First.Should().Be(mediaItems[2]);
+            result[2].First.Should().Be(mediaItems[3]);
+            result[2].Additional[0].Should().Be(mediaItems[4]);
+        }
+
+        [Test]
+        public void Grouped_Grouped()
+        {
+            var mediaItems = new List<MediaItem>
+            {
+                NamedEpisode("Episode 1 (1)"),
+                NamedEpisode("Episode 2 (2)"),
+                NamedEpisode("Episode 3 (1)"),
+                NamedEpisode("Episode 4 (2)"),
+            };
+
+            List<GroupedMediaItem> result = MultiPartEpisodeGrouper.GroupMediaItems(mediaItems);
+
+            result.Count.Should().Be(2);
+            result[0].First.Should().Be(mediaItems[0]);
+            result[0].Additional[0].Should().Be(mediaItems[1]);
+            result[1].First.Should().Be(mediaItems[2]);
+            result[1].Additional[0].Should().Be(mediaItems[3]);
+        }
+
+        private static Episode NamedEpisode(string title) =>
+            new()
+            {
+                EpisodeMetadata = new List<EpisodeMetadata>
+                {
+                    new() { Title = title }
+                }
+            };
+    }
+}

ErsatzTV.Core/Scheduling/MultiPartEpisodeGrouper.cs

@@ -24,6 +24,13 @@ namespace ErsatzTV.Core.Scheduling
                     if (match.Success)
                     {
                         var number = int.Parse(match.Groups[1].Value);
+                        if (number <= lastNumber && group != null)
+                        {
+                            groups.Add(group);
+                            group = null;
+                            lastNumber = 0;
+                        }
+
                         if (number == lastNumber + 1)
                         {
                             if (lastNumber == 0)
@@ -46,6 +53,11 @@ namespace ErsatzTV.Core.Scheduling
 
                             lastNumber = number;
                         }
+                        else
+                        {
+                            // this should never happen
+                            throw new InvalidOperationException($"Bad shuffle state; unexpected number {number} after {lastNumber}");
+                        }
                     }
                     else
                     {