VisibleCommentScope says at the top of the class that its callers must
already have established that the viewer may see the file. The public
listing's comment endpoint establishes only the guest half of that — the
file is reachable without an account — and then hands $request->user()
straight to the authenticated reading.
For anyone the file's own gate would refuse, that reading is far too
wide. A staff account outside its library, or one holding no file
permission at all, read the file's staff-only notes; a client the file
was never shared with read the messages staff addressed to that file's
clients. Both get a 403 from GET /files/{file}/comments and needed only
to ask the public URL instead.
The endpoint now asks the file's own gate which reading applies. A reader
it admits sees no less than before. A reader it refuses gets what a
visitor gets, widened by their own comments — which is what this
controller has always promised them, and all it promised. The
held-comment rule moves into a method both readings share rather than
being restated.
The same root reaches PATCH and DELETE /comments/{comment}, which bind a
comment rather than a file and so never authorized `view` on it either.
They answer with the thread, and now with the one the file's gate allows.
Refusing them outright would be wrong: somebody who commented through
the public page is exactly the person entitled to edit their own words.
denkfabrik-li