Fixed: Subtitle tags from existing subtitle files being lost during rename

Closes #5577

src/NzbDrone.Core/Extras/Subtitles/ExistingSubtitleImporter.cs

@@ -1,4 +1,4 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using NLog;
@@ -78,6 +78,7 @@ namespace NzbDrone.Core.Extras.Subtitles
                                            EpisodeFileId = localEpisode.Episodes.First().EpisodeFileId,
                                            RelativePath = series.Path.GetRelativePath(possibleSubtitleFile),
                                            Language = LanguageParser.ParseSubtitleLanguage(possibleSubtitleFile),
+                                           LanguageTags = LanguageParser.ParseLanguageTags(possibleSubtitleFile),
                                            Extension = extension
                                        };
 

src/NzbDrone.Core/Extras/Subtitles/SubtitleService.cs

@@ -185,9 +185,9 @@ namespace NzbDrone.Core.Extras.Subtitles
                 var subFile = new SubtitleFile
                 {
                     Language = language,
-                    Extension = extension
+                    Extension = extension,
+                    LanguageTags = languageTags
                 };
-                subFile.LanguageTags = languageTags.ToList();
                 subFile.RelativePath = PathExtensions.GetRelativePath(sourceFolder, file);
                 subtitleFiles.Add(subFile);
             }

src/NzbDrone.Core/Parser/LanguageParser.cs

@@ -226,7 +226,7 @@ namespace NzbDrone.Core.Parser
             return Language.Unknown;
         }
 
-        public static IEnumerable<string> ParseLanguageTags(string fileName)
+        public static List<string> ParseLanguageTags(string fileName)
         {
             try
             {
@@ -235,14 +235,14 @@ namespace NzbDrone.Core.Parser
                 var languageTags = match.Groups["tags"].Captures.Cast<Capture>()
                     .Where(tag => !tag.Value.Empty())
                     .Select(tag => tag.Value.ToLower());
-                return languageTags;
+                return languageTags.ToList();
             }
             catch (Exception ex)
             {
                 Logger.Debug(ex, "Failed parsing language tags from subtitle file: {0}", fileName);
             }
 
-            return Enumerable.Empty<string>();
+            return new List<string>();
         }
 
         private static List<Language> RegexLanguage(string title)