tests/test-log-exthook.t

status: intersect matcher with narrow matcher instead of filtering afterwards

I seem to have done a very naive move of the code from the narrow
extension into core in e411774a2e0f (narrow: move status-filtering to
core and to ctx, 2018-08-02). It seems obvious that a better way is to
intersect the matchers.

Note that this means that when requesting status for the working
directory in a narrow repo, we now pass the narrow matcher (possibly
intersected with a user-provided matcher) into _buildstatus() and then
into dirstate.status() and dirstate.walk(), which will the intersect
it again with the narrow matcher. That's functionally fine, but
wasteful. I hope to later remove the dirstate wrapping that adds the
second layer of matcher intersection.

Differential Revision: https://phab.mercurial-scm.org/D4897

Test hg log changeset printer external hook
-------------------------------------------

  $ cat > $TESTTMP/logexthook.py <<EOF
  > from __future__ import absolute_import
  > import codecs
  > from mercurial import (
  >   commands,
  >   logcmdutil,
  >   repair,
  > )
  > def rot13description(self, ctx):
  >     summary = codecs.encode("summary", 'rot-13')
  >     description = ctx.description().strip().splitlines()[0].encode('rot13')
  >     self.ui.write("%s:     %s\n" % (summary, description))
  > def reposetup(ui, repo):
  >     logcmdutil.changesetprinter._exthook = rot13description
  > EOF

Prepare the repository

  $ hg init empty
  $ cd empty
  $ touch ROOT
  $ hg commit -A -m "Root" ROOT

  $ touch a b c
  $ hg commit -A -m "Add A, B, C" a b c

Check the log

  $ hg log --config extensions.t=$TESTTMP/logexthook.py
  changeset:   1:70fc82b23320
  tag:         tip
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  fhzznel:     Nqq N, O, P
  summary:     Add A, B, C
  
  changeset:   0:b00443a54871
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  fhzznel:     Ebbg
  summary:     Root
  
Check that exthook is working with graph log too

  $ hg log -G --config extensions.t=$TESTTMP/logexthook.py
  @  changeset:   1:70fc82b23320
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  fhzznel:     Nqq N, O, P
  |  summary:     Add A, B, C
  |
  o  changeset:   0:b00443a54871
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     fhzznel:     Ebbg
     summary:     Root