FileMonitor

DogmaDragon · August 22, 2026, 2:00am

DupFileManager, FileMonitor, RenameFile: bind the exception in retry handlers

main ← johnkattenhorn:fix/unbound-exception-variable

opened 07:41PM - 14 Aug 26 UTC

### The problem Each retry loop in `StashPluginHelper.py` has two exception han…dlers: a narrow one for connection errors, and a broad one for everything else. Both build the same log message including `{e}` — but only the broad handler binds the name with `as e`. Because the sibling handler binds `e` as a function local, the narrow handler raises `UnboundLocalError` while formatting its own log message. That propagates out of the retry loop, so a dropped connection — the exact condition the loop exists to survive — aborts the operation on the first failure and reports the wrong error. Reproduction, matching the structure in the source: ```python def retry(): for i in range(3): try: raise ConnectionResetError("connection dropped") except (ConnectionResetError): print(f"retrying: {e}") # UnboundLocalError except Exception as e: print(f"retrying: {e}") ``` ### Scope 13 sites across the three plugins that vendor `StashPluginHelper.py`: | File | Lines | |---|---| | `plugins/DupFileManager/StashPluginHelper.py` | 522, 713, 748, 769 | | `plugins/FileMonitor/StashPluginHelper.py` | 522, 713, 748, 769 | | `plugins/RenameFile/StashPluginHelper.py` | 522, 713, 748, 769 | | `plugins/DupFileManager/DupFileManager.py` | 351 | Those are the `mergeMetadata`, `addTag`, `updateScene` and `destroyScene` retry loops in each copy of the helper, plus `setTagId_withRetry` in DupFileManager. Every change is the same one-token edit — adding `as e` to a handler that already interpolated `e`. No behaviour changes beyond the retry path now working as written. ### Testing Tested against a clean Stash **v0.31.1** instance in Docker with a two-scene library, driving the plugin helper through the real plugin entry path (plugin JSON on stdin, `server_connection` context). Fault injection: `mergeMetadata` was made to raise `ConnectionResetError` on its first two attempts, then succeed — the scenario the retry loop is written for. Same test run against both the current `main` and this branch: ``` RESULT[original]: UnboundLocalError: cannot access local variable 'e' where it is not associated with a value (attempts = 1) RESULT[patched]: survived the resets and completed; attempts = 3 ``` `main` aborts on the first reset. With the fix, the loop retries and completes as intended. Also confirmed: - A normal (non-failing) `mergeMetadata` between two scenes behaves identically before and after — no regression in the success path. - AST pass over the whole repository: zero remaining `except` handlers that reference an unbound `e`. - All four modified files compile. `plugins/starIdentifier/star_identifier.py` matches this pattern at first glance but is **not** affected — `load_encodings()` binds `e = Exception(...)` before the `try`, so its handler resolves the name from the enclosing scope. Deliberately left alone. ### Note for maintainers `StashPluginHelper.py` is vendored into three plugins and the copies have already drifted — DupFileManager's differs from the other two. This fix is applied to all three. Worth considering whether that file wants a single shared home. ### LLM-assisted contribution disclosure Per the repository's contribution policy: this change was prepared with LLM assistance (Claude). The diff has been reviewed by me, the testing described above was carried out and its results are reproduced verbatim, and I take full responsibility for the change and its license compliance.

@David-Maisonave would you be interested in reviewing it?