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