parser: add helper function that constructs parsed tree from template This function will be used as follows: build('only(_, _)', x, y) See the next patch for details.

patch: take messages out of the function so that extensions can add entries Extensions will want to have interactive thing for more operations or particulary want to show more verbs. So this patch takes out the message thing from the function so that extensions can add verbs to this. The curses one is also not in any function so extensions can add more actions and verbs there. Differential Revision: https://phab.mercurial-scm.org/D567

run-tests: allow bisecting a different repo Add `--bisect-repo` flag which accepts a different repo to bisect. 3rd party extensions may reuse `run-tests.py` from core to run tests. Test failure could be caused by either a core hg change or the 3rd party extension code itself. Having a way to specify which repo to bisect is useful. Differential Revision: https://phab.mercurial-scm.org/D578

run-tests: extract prefix of bisect commands to a variable This does not change any logic. Differential Revision: https://phab.mercurial-scm.org/D577

run-tests: pass --with-hg to run-tests.py command used by bisect This makes `run-tests.py -l test-run-tests.t` 23 seconds faster on my laptop. Inside the test, `$ rt --known-good-rev=0 test-bisect.t` took 24.9 seconds before, and 1.2 seconds after. Differential Revision: https://phab.mercurial-scm.org/D576

import-checker: allow relative import a module being checked This would make the checker more friendly for 3rd-party code. For example, In remotefilelog/x.py, it may have: from . import shallowutils That could trigger "relative import of stdlib module" if "remotefilelog" was installed in the system. If the module being checked conflicts with the system module, it makes sense to not treat that module as system module. This patch makes it so. Differential Revision: https://phab.mercurial-scm.org/D552

merge: move some of the logic in batchget() to workingfilectx We will use this logic in two places with in-memory merge. Differential Revision: https://phab.mercurial-scm.org/D444

filemerge: add _restorebackup Differential Revision: https://phab.mercurial-scm.org/D404

filemerge: reduce creation of tempfiles until needed This restricts the creation of temporary files to just `_xmerge`, when we call an external tool. Differential Revision: https://phab.mercurial-scm.org/D403

filemerge: add `_workingpath` This reduces any reliance on `a`. Differential Revision: https://phab.mercurial-scm.org/D401