largefiles: only cache largefiles in new heads This fixes a serious performance regression in largefiles introduced in Mercurial 2.1. Caching new largefiles on pull is necessary, because otherwise largefiles will be missing (and unable to be downloaded) when the user tries to merge or rebase a new head with an old one. But this is an expensive operation and should only be done for heads that are new from the pull, rather than on all heads in the repository.

merge with stable

mq: restore _branchtags() fast path (issue3223) Since a5917346c72e, mq saves the nodeid of the first applied patch to cache/branchheads, which breaks the optimized cache handling introduced in fbf8320f25c8. The problem is the revision being committed is appended to mqrepo.applied after the commit succeeds, which means mqrepo._branchtags() performs a regular update and write the first applied patch to the branch cache. One solution is to set a context variable _committingpatch on the mqrepo while it is committing a patch and to take it in account when deciding to fast-path mqrepo._branchtags(). Not really elegant but it works. The changes to test-mq-caches.t reverse changes introduced by a5917346c72e. The cache should not have been updated with mq records. The changes to test-keyword.t are indirectly caused by a5917346c72e. Reported and analyzed by Yuya Nishihara <yuya@tcha.org> Notes: - qpush still makes a slow path _branchtags() call when checking heads. Maybe this can be optimized. - be careful when merging this patch in default as secretcommit() was renamed newcommit() right after the end of the code freeze.