scmutil: introduce filterrequirements() to split reqs into wc and store ones In upcoming patches where we try to implement requirements in store, we will need a mechanism to split all requirements on some basis and decide which one goes to `.hg/requires` and which one goes to `.hg/store/requires`. This patch introduce a separate function for that. Filtering logic for now is put under an `if False:`. In upcoming patches it will be removed. Differential Revision: https://phab.mercurial-scm.org/D8913

remotefilelog: acquire lock before writing requirements on clone Performing a shallow clone in remotefilelog does not acquire lock. This leads to following warning when we try to write some requirements in store: ``` --- /home/gps/src/hg-committed/tests/test-remotefilelog-share.t +++ /home/gps/src/hg-committed/tests/test-remotefilelog-share.t#safe.err @@ -28,6 +28,7 @@ $ hgcloneshallow ssh://user@dummy/master source --noupdate -q + devel-warn: write with no lock: "requires" at: /home/gps/src/hg-committed/mercurial/scmutil.py:1505 (writerequires) $ hg share source dest updating working directory 1 files updated, 0 files merged, 0 files removed, 0 files unresolved ``` Let's lock before writing the requirements file. Another solution which I can think of is not warn about missing lock when writing to requires file in store. Differential Revision: https://phab.mercurial-scm.org/D8952

grep: make -frREV follow history from the specified revision (BC) This is close to what "log -frREV" will do, and is backported from 8b4b9ee6001a, "log: make -fr show complete history from the given revs" except for the "del opts['follow']" bit. I'm planning to rewrite cmdutil.walkchangerevs() to share the core logic with logcmdutil, and this is the first step towards that. There are still many broken tests, but the fundamental behavior should be fixed by this patch. .. bc:: `hg grep -fr REV` now follows history from the specified `REV`, works in the same way as `hg log -fr REV`. The previous behavior was to limit the search space to `REV` while following the history.

cmdutil: make walkchangerevs() gracefully handle wdir parents This code will be completely rewritten, but test-grep.t would fail without fixing it.

grep: fix --follow with no --diff nor --rev to not fall back to plain grep Before, "grep --follow" would only print matches in the working directory. Since --follow is the option to specify the search space, it should disable the plain (i.e. wdir) grep.

test-grep: add tests for --follow with/without --diff and/or paths This tests the behavior of cmdutil.walkchangerevs(). I'm going to rewrite cmdutil.walkchangerevs() to leverage the "log -f" logic, but the code coverage looked quite small. And the history traversal of "grep -f" goes wrong in various ways.