hghave: add a check for the `xz` compression utility
This isn't install by default on Mac, which causes a test failure. The logic
for avoiding the command is a little goofy, but nested `#if` isn't supported,
and it still seems worth running the hg command to see if anything explodes.
With this, the py3 tests run (almost) cleanly on 10.14.6:
# Ran 835 tests, 58 skipped, 1 failed.
Alas, the mac-packaging test is skipped because it's slow. The failure here is
in test-releasenotes-merging.t, complaining about not being able to import the
`fuzzywuzzy` module. I have it installed on py3 (thus the test isn't skipped),
but not on py2. So there must be some unintended cross pollination here when
running `hg` commands.
Differential Revision: https://phab.mercurial-scm.org/D7374
$ hg init repo
$ cd repo
$ echo 0 > a
$ hg ci -qAm 0
$ for i in 5 8 14 43 167; do
> hg up -q 0
> echo $i > a
> hg ci -qm $i
> done
$ cat <<EOF >> .hg/hgrc
> [alias]
> l = log -T '{rev}:{shortest(node,1)}\n'
> EOF
$ hg l
5:00f
4:7ba5d
3:7ba57
2:72
1:9
0:b
$ cat <<EOF >> .hg/hgrc
> [experimental]
> revisions.disambiguatewithin=not 4
> EOF
$ hg l
5:00
4:7ba5d
3:7b
2:72
1:9
0:b
9 was unambiguous and still is
$ hg l -r 9
1:9
7 was ambiguous and still is
$ hg l -r 7
abort: 00changelog.i@7: ambiguous identifier!
[255]
7b is no longer ambiguous
$ hg l -r 7b
3:7b
$ cd ..