revpair: simplify revpair by always relying on smartset.first/last I thinkt the code was written the way it was because it comes from 97b2f26dfc43 (revpair: smartset compatibility, 2014-03-20) and the first/last methods came only later, in 228b0aafb1ce (smartset: add first and last methods, 2014-10-06). Differential Revision: https://phab.mercurial-scm.org/D5687

grep: use set instead of dict with dummy value Differential Revision: https://phab.mercurial-scm.org/D5633

grep: don't look up copy info unless --follow is given If no --follow was given, then the "copy" variable will become None. In that case we would still look up the copy information from the filelog and then ignore it. Let's avoid even looking it up. Differential Revision: https://phab.mercurial-scm.org/D5620

hghave: let OSError with ENOENT through like any other Before this patch, if we get an OSError with ENOENT, we would not re-raise it and would instead run into an undefined variable ("p") soon thereafter. Differential Revision: https://phab.mercurial-scm.org/D5631

cleanup: delete lots of unused local variables These were found by IntelliJ. There are many more, but these seemed pretty safe. Differential Revision: https://phab.mercurial-scm.org/D5629

localrepo: use context manager for lock and transaction in commitctx() Differential Revision: https://phab.mercurial-scm.org/D5624

localrepo: use context manager for locks in commit() Differential Revision: https://phab.mercurial-scm.org/D5623

localrepo: use context manager for transaction in commit() A side-effect is that the transaction is released a little earlier, so the "commit message saved in ..." messages now comes after the "rollback completed" message. That seems slightly better to me. Differential Revision: https://phab.mercurial-scm.org/D5622

commit: print "commit message saved in" message also if bookmark update fails The bookmark update is done within the same transaction, so if fails, the commit will also be rolled back. I just happened to notice this while messing with this code; we have not had reports of crashing bookmark updates from our users. The same applies to the clearing of the merge state, although I don't think that's currently tied into the transaction. Differential Revision: https://phab.mercurial-scm.org/D5621

remotefilelog: remove pointless return statement from constructor Differential Revision: https://phab.mercurial-scm.org/D5630

revset: support ranges in #generations relation

tests: fix module-import warnings in test-update-atomic.t These were caught by test-check-module-imports.t on Python 3. This should also make python3-buildbot green again. Differential Revision: https://phab.mercurial-scm.org/D5674

py3: use dict.items() instead of dict.iteritems() in tests/test-lfs-server.t dict.iteritems() is not present on Python 3. Differential Revision: https://phab.mercurial-scm.org/D5673

py3: add b'' prefixes in tests/test-lfs-serve.t # skip-blame because just b'' prefixes Differential Revision: https://phab.mercurial-scm.org/D5672

py3: add b'' prefixes in doc/check-seclevel.py # skip-blame because just b'' prefixes Differential Revision: https://phab.mercurial-scm.org/D5670