warn and possibly require an override flag if the upstream tag has changed #258
Description
We've seen several instances where people update their upstream repo, and then change the versioned tag for the repo instead of making a new release. This is very poor practice as it makes the contents of a tagged version different depending on when you query it. More in relationship to bloom it causes debian increments to hide upstream changes as debian packaging updates. If something changes upstream it should be in a patch release.
Right now if you rerun bloom it just reimports all the time whether or not the tag has changed. To avoid this bloom could warn or require an option to reimport the same tag from upstream. @dirk-thomas is writing a guideline to be added to release docs.
Marking as untargeted enhancement as it's more for cleanliness than breaking anything at the moment.