GuessitException: FixParentFolderReplacingTitle corrupts rebulk when folder ends with codec digit (e.g. AC-3)

[Mika3578]

Summary

Post-processing can abort with guessit.api.GuessitException / ValueError: list.remove(x): x not in list when a release folder name ends with a codec/quality suffix that looks like "separator + digits" (classic example: AC-3).

This is a Medusa custom-rules bug, not an upstream Guessit parser failure: stock Guessit parses the same string successfully.

Root cause (generic)

1. FixParentFolderReplacingTitle treats any parent folder matching (_|\W)\d+$ as "folder ends with a number" (intended for cases like /Comedy 23/Show.S01E01.mkv).
2. That regex also matches technical tails such as AC-3 (-3).
3. The rule then mutates an existing match in place:

   episode_title[0].name = 'title'

   without properly removing/re-adding it in rebulk's indexes → _name_dict desync.
4. A later rule (AvoidMultipleValuesRule, consequence RemoveMatch) calls matches.remove(match) → ValueError: list.remove(x): x not in list → wrapped as GuessitException.
5. NameParser / _analyze_name only catches InvalidNameException / InvalidShowException, so the exception bubbles up and kills the post-processor for that item.

Generic formula: in-place match.name mutation in Medusa rules + subsequent RemoveMatch = Guessit crash. Frequent trigger = false positive of ends_with_digit on codec/channel suffixes.

Reproduction

Path shape (folder + file both end with AC-3):

tv\Capital - Des vacances de rêve 30 % moins chères, oui, c'est vraiment possible ! 2023 French HDTV 720p AVC MKV AC-3\Capital - Des vacances de rêve 30 % moins chères, oui, c'est vraiment possible ! 2023 French HDTV 720p AVC MKV AC-3.mkv

Observed with Medusa's customized Guessit API (medusa.name_parser.rules); plain guessit.guessit(...) without Medusa rules does not crash.

Confirmed locally:

• Enabling Medusa rules() → crash
• Culprit interaction: FixParentFolderReplacingTitle then AvoidMultipleValuesRule
• Skipping FixParentFolderReplacingTitle when the folder ends with a codec-like suffix → parse succeeds (title=Capital)

Suggested fix

In medusa/name_parser/rules/rules.py (FixParentFolderReplacingTitle):

• Do not treat codec/channel tails as "ends with digit" (AC-3, EAC3, DDP5.1, H.264, x265, …).
• Prefer not mutating match.name in place; use proper remove/append so rebulk indexes stay consistent.

Optional hardening:

• Catch GuessitException in the name parser and map it to InvalidNameException so one bad name cannot abort the whole post-process run.

Environment

• Guessit 3.4.2 (vendored)
• Medusa custom rules in medusa/name_parser/rules/rules.py
• Log excerpt: POSTPROCESSOR :: Exception generated: An internal error has occured in guessit. / ValueError: list.remove(x): x not in list in ext/rebulk/match.py