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
Test update.requiredest
$ cd $TESTTMP
$ cat >> $HGRCPATH <<EOF
> [commands]
> update.requiredest = True
> EOF
$ hg init repo
$ cd repo
$ echo a >> a
$ hg commit -qAm aa
$ hg up
abort: you must specify a destination
(for example: hg update ".::")
[255]
$ hg up .
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ HGPLAIN=1 hg up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg --config commands.update.requiredest=False up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ..
Check update.requiredest interaction with pull --update
$ hg clone repo clone
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd repo
$ echo a >> a
$ hg commit -qAm aa
$ cd ../clone
$ hg pull --update
abort: update destination required by configuration
(use hg pull followed by hg update DEST)
[255]