MergeUtils: Fixing dictionary merge for null values

Kyoo.Common/Utility/Merger.cs

@@ -79,7 +79,16 @@ namespace Kyoo
 			if (second == null)
 				return first;
 			foreach ((T key, T2 value) in second)
-				hasChanged |= first.TryAdd(key, value);
+			{
+				bool success = first.TryAdd(key, value);
+				hasChanged |= success;
+				
+				if (success || first[key]?.Equals(default) == false || value?.Equals(default) != false)
+					continue;
+				first[key] = value;
+				hasChanged = true;
+			}
+
 			return first;
 		}
 
@@ -123,7 +132,7 @@ namespace Kyoo
 			hasChanged = false;
 			if (second == null)
 				return first;
-			hasChanged = second.Any(x => !x.Value.Equals(first[x.Key]));
+			hasChanged = second.Any(x => x.Value?.Equals(first[x.Key]) == false);
 			foreach ((T key, T2 value) in first)
 				second.TryAdd(key, value);
 			return second;

Kyoo.TheMovieDb/ProviderTmdb.cs

@@ -157,7 +157,7 @@ namespace Kyoo.TheMovieDb
 			
 			TMDbClient client = new(_apiKey.Value.ApiKey);
 			return (await client.GetTvEpisodeAsync(id, episode.SeasonNumber.Value, episode.EpisodeNumber.Value))
-				.ToEpisode(id, Provider);
+				?.ToEpisode(id, Provider);
 		}
 		
 		/// <summary>

tests/Kyoo.Tests/Utility/MergerTests.cs

@@ -455,5 +455,85 @@ namespace Kyoo.Tests.Utility
 			Merger.Merge(first, second);
 			// This should no call the setter of first so the test should pass.
 		}
+		
+		[Fact]
+		public void MergeDictionaryNullValue()
+		{
+			Dictionary<int, string> first = new()
+			{
+				[Images.Logo] = "logo",
+				[Images.Poster] = null
+			};
+			Dictionary<int, string> second = new()
+			{
+				[Images.Poster] = "new-poster",
+				[Images.Thumbnail] = "thumbnails"
+			};
+			IDictionary<int, string> ret = Merger.MergeDictionaries(first, second, out bool changed);
+			Assert.True(changed);
+			Assert.Equal(3, ret.Count);
+			Assert.Equal("new-poster", ret[Images.Poster]);
+			Assert.Equal("thumbnails", ret[Images.Thumbnail]);
+			Assert.Equal("logo", ret[Images.Logo]);
+		}
+		
+		[Fact]
+		public void MergeDictionaryNullValueNoChange()
+		{
+			Dictionary<int, string> first = new()
+			{
+				[Images.Logo] = "logo",
+				[Images.Poster] = null
+			};
+			Dictionary<int, string> second = new()
+			{
+				[Images.Poster] = null,
+			};
+			IDictionary<int, string> ret = Merger.MergeDictionaries(first, second, out bool changed);
+			Assert.False(changed);
+			Assert.Equal(2, ret.Count);
+			Assert.Null(ret[Images.Poster]);
+			Assert.Equal("logo", ret[Images.Logo]);
+		}
+		
+		[Fact]
+		public void CompleteDictionaryNullValue()
+		{
+			Dictionary<int, string> first = new()
+			{
+				[Images.Logo] = "logo",
+				[Images.Poster] = null
+			};
+			Dictionary<int, string> second = new()
+			{
+				[Images.Poster] = "new-poster",
+				[Images.Thumbnail] = "thumbnails"
+			};
+			IDictionary<int, string> ret = Merger.CompleteDictionaries(first, second, out bool changed);
+			Assert.True(changed);
+			Assert.Equal(3, ret.Count);
+			Assert.Equal("new-poster", ret[Images.Poster]);
+			Assert.Equal("thumbnails", ret[Images.Thumbnail]);
+			Assert.Equal("logo", ret[Images.Logo]);
+		}
+		
+		[Fact]
+		public void CompleteDictionaryNullValueNoChange()
+		{
+			Dictionary<int, string> first = new()
+			{
+				[Images.Logo] = "logo",
+				[Images.Poster] = null
+			};
+			Dictionary<int, string> second = new()
+			{
+				[Images.Poster] = null,
+			};
+			IDictionary<int, string> ret = Merger.CompleteDictionaries(first, second, out bool changed);
+			Assert.False(changed);
+			Assert.Equal(2, ret.Count);
+			Assert.Null(ret[Images.Poster]);
+			Assert.Equal("logo", ret[Images.Logo]);
+		}
 	}
 }