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
https://bz.mercurial-scm.org/1877
$ hg init a
$ cd a
$ echo a > a
$ hg add a
$ hg ci -m 'a'
$ echo b > a
$ hg ci -m'b'
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg book main
$ hg book
* main 0:cb9a9f314b8b
$ echo c > c
$ hg add c
$ hg ci -m'c'
created new head
$ hg book
* main 2:d36c0562f908
$ hg heads
changeset: 2:d36c0562f908
bookmark: main
tag: tip
parent: 0:cb9a9f314b8b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: c
changeset: 1:1e6c11564562
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: b
$ hg up 1e6c11564562
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark main)
$ hg merge main
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg book
main 2:d36c0562f908
$ hg ci -m'merge'
$ hg book
main 2:d36c0562f908
$ cd ..