Something I've noticed in the past but which seems to have become systematic with the latest arcanist version:
- create a review request ("differential revision") with all fields filled in, including the repository the diff applies to.
- use arcanist to upload an updated raw diff, e.g. arc diff --update DXXXX --raw < foo.diff --message "raw diff updated with arc" .
- use "Edit Revision" to check the repository field (why is this info not shown?) .
When I follow these steps, the repository information has been lost.
I notice that it apparently has to be entered anew when updating a diff through the web interface.
In itself it is fine that it's possible to update a diff and the repository information, but IMHO it shouldn't be required (or else arc diff should provide an argument to provide this data along with the new diff).