Determine merge container better (See desc) (#1482)

[yt-dlp.git] / yt_dlp / __init__.py

diff --git a/yt_dlp/__init__.py b/yt_dlp/__init__.py
index 4024b6ba1e227bb4b9ae5495550156a4d329f3d5..317dd26231cea426a8ffa8636e701d70ca5922fc 100644 (file)
--- a/yt_dlp/__init__.py
+++ b/yt_dlp/__init__.py
@@ -228,7 +228,8 @@ def validate_minmax(min_val, max_val, min_name, max_name=None):
         validate_regex('format sorting', f, InfoExtractor.FormatSort.regex)
 
     # Postprocessor formats
-    validate_in('merge output format', opts.merge_output_format, FFmpegMergerPP.SUPPORTED_EXTS)
+    validate_regex('merge output format', opts.merge_output_format,
+                   r'({0})(/({0}))*'.format('|'.join(map(re.escape, FFmpegMergerPP.SUPPORTED_EXTS))))
     validate_regex('audio format', opts.audioformat, FFmpegExtractAudioPP.FORMAT_RE)
     validate_in('subtitle format', opts.convertsubtitles, FFmpegSubtitlesConvertorPP.SUPPORTED_EXTS)
     validate_regex('thumbnail format', opts.convertthumbnails, FFmpegThumbnailsConvertorPP.FORMAT_RE)