Fix incorrect year on local trailers

Emby.Server.Implementations/Library/Resolvers/ExtraResolver.cs

@@ -32,8 +32,8 @@ namespace Emby.Server.Implementations.Library.Resolvers
             : base(logger, namingOptions, directoryService)
         {
             _namingOptions = namingOptions;
-            _trailerResolvers = new IItemResolver[] { new GenericVideoResolver<Trailer>(logger, namingOptions, directoryService) };
-            _videoResolvers = new IItemResolver[] { this };
+            _trailerResolvers = [new GenericVideoResolver<Trailer>(logger, namingOptions, directoryService, parseName: true)];
+            _videoResolvers = [this];
         }
 
         protected override Video Resolve(ItemResolveArgs args)

Emby.Server.Implementations/Library/Resolvers/GenericVideoResolver.cs

@@ -2,6 +2,7 @@
 
 using Emby.Naming.Common;
 using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Library;
 using MediaBrowser.Controller.Providers;
 using Microsoft.Extensions.Logging;
 
@@ -14,15 +15,25 @@ namespace Emby.Server.Implementations.Library.Resolvers
     public class GenericVideoResolver<T> : BaseVideoResolver<T>
         where T : Video, new()
     {
+        private readonly bool _parseName;
+
         /// <summary>
         /// Initializes a new instance of the <see cref="GenericVideoResolver{T}"/> class.
         /// </summary>
         /// <param name="logger">The logger.</param>
         /// <param name="namingOptions">The naming options.</param>
         /// <param name="directoryService">The directory service.</param>
-        public GenericVideoResolver(ILogger logger, NamingOptions namingOptions, IDirectoryService directoryService)
+        /// <param name="parseName">Whether to parse the file name for metadata such as the year.</param>
+        public GenericVideoResolver(ILogger logger, NamingOptions namingOptions, IDirectoryService directoryService, bool parseName = false)
             : base(logger, namingOptions, directoryService)
         {
+            _parseName = parseName;
+        }
+
+        /// <inheritdoc />
+        protected override T Resolve(ItemResolveArgs args)
+        {
+            return ResolveVideo<T>(args, _parseName);
         }
     }
 }

MediaBrowser.Controller/Entities/BaseItem.cs

@@ -1557,6 +1557,19 @@ namespace MediaBrowser.Controller.Entities
 
                 i.OwnerId = ownerId;
                 i.ParentId = Guid.Empty;
+
+                // Extras (e.g. trailers) frequently have no reliable date metadata of their own and
+                // would otherwise fall back to the file's container creation date. Inherit the owner's
+                // year/premiere date when the extra doesn't have one, so it stays consistent with the
+                // media it belongs to. Setting it before the refresh means the media info provider
+                // won't overwrite it from the file creation date.
+                if (!i.ProductionYear.HasValue && item.ProductionYear.HasValue)
+                {
+                    i.ProductionYear = item.ProductionYear;
+                    i.PremiereDate ??= item.PremiereDate;
+                    subOptions.ForceSave = true;
+                }
+
                 return RefreshMetadataForOwnedItem(i, true, subOptions, cancellationToken);
             });
 

tests/Jellyfin.Server.Implementations.Tests/Library/LibraryManager/FindExtrasTests.cs

@@ -305,6 +305,47 @@ public class FindExtrasTests
         Assert.Empty(extras);
     }
 
+    [Fact]
+    public void FindExtras_TrailerWithYearInFilename_SetsProductionYearFromFilename()
+    {
+        var owner = new Movie { Name = "Up", Path = "/movies/Up/Up.mkv" };
+        var paths = new List<string>
+        {
+            "/movies/Up/Up.mkv",
+            "/movies/Up/trailers"
+        };
+
+        _fileSystemMock.Setup(f => f.GetFiles(
+                "/movies/Up/trailers",
+                It.IsAny<string[]>(),
+                false,
+                false))
+            .Returns(new List<FileSystemMetadata>
+            {
+                new()
+                {
+                    FullName = "/movies/Up/trailers/Trailer 1 (2013).mkv",
+                    Name = "Trailer 1 (2013).mkv",
+                    IsDirectory = false
+                }
+            }).Verifiable();
+
+        var files = paths.Select(p => new FileSystemMetadata
+        {
+            FullName = p,
+            Name = Path.GetFileName(p),
+            IsDirectory = !Path.HasExtension(p)
+        }).ToList();
+
+        var extras = _libraryManager.FindExtras(owner, files, new DirectoryService(_fileSystemMock.Object)).ToList();
+
+        _fileSystemMock.Verify();
+        var trailer = Assert.Single(extras);
+        Assert.Equal(ExtraType.Trailer, trailer.ExtraType);
+        Assert.Equal(typeof(Trailer), trailer.GetType());
+        Assert.Equal(2013, trailer.ProductionYear);
+    }
+
     [Fact]
     public void FindExtras_SeriesWithTrailers_FindsCorrectExtras()
     {