templatekw: choose {latesttag} by len(changes), not date (
issue5659)
As Augie reported in the bug, the current heuristic of choosing the
best tag of a merge commit by taking the one with newest tag (in terms
of tagging date) currently fails in the Mercurial repo itself. Copying
the example from Yuya:
$ hg glog -T '{node|short} {latesttag}+{latesttagdistance}\n' \
-r '4.2.3: & (merge() + parents(merge()) + tag())'
o
02a745c20121 4.2.3+5
|\
| o
86aca74a063b 4.2.3+4
| |\
| | o
e6d8ee3c9ec3 4.3-rc+109
| | |
| | ~
o |
a3ce07e2dde5 4.3.1+2
: |
o |
3fee7f7d2da0 4.3.1+0
|/
o
98e990bb7330 4.2.3+3
|\
| ~
o
506d7e48fbe6 4.2.3+2
:
o
943c91326b23 4.2.3+0
|
~
It seems to me like the best choice is the tag with the smallest
number of changes since it (across all paths, not the longest single
path). So that's what this patch does, even though it's
costly. Best-of-5 timings for Yuya's command above shows a slowdown
from 1.293s to 1.610s. We can optimize it later.
Differential Revision: https://phab.mercurial-scm.org/D447
tests: use graph log in {latesttag} tests
The tests are much easier to read if one does not have to re-read the
setup part all the time to understand the graph shape.
Differential Revision: https://phab.mercurial-scm.org/D446
demandimport: disable if chg is being used
In chg's case, making modules lazily loaded could actually slow down things
since chg pre-imports them. Therefore disable demandimport if chg is being
used.
This is not done by setting `HGDEMANDIMPORT` chg client-side because that
has side-effects on child processes (hooks, etc).
Differential Revision: https://phab.mercurial-scm.org/D351