strip: add a delayedstrip method that works in a transaction For long, the fact that strip does not work inside a transaction and some code has to work with both obsstore and fallback to strip lead to duplicated code like: with repo.transaction(): .... if obsstore: obsstore.createmarkers(...) if not obsstore: repair.strip(...) Things get more complex when you want to call something which may call strip under the hood. Like you cannot simply write: with repo.transaction(): .... rebasemod.rebase(...) # may call "strip", so this doesn't work But you do want rebase to run inside a same transaction if possible, so the code may look like: with repo.transaction(): .... if obsstore: rebasemod.rebase(...) obsstore.createmarkers(...) if not obsstore: rebasemod.rebase(...) repair.strip(...) That's ugly and error-prone. Ideally it's possible to just write: with repo.transaction(): rebasemod.rebase(...) saferemovenodes(...) This patch is the first step towards that. It adds a "delayedstrip" method to repair.py which maintains a postclose callback in the transaction object.