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
% removeancestorsfrom(), example 1
remaining (sorted): [5, 6, 8, 9]
% removeancestorsfrom(), example 2
remaining (sorted): [11, 12, 13, 14]
% removeancestorsfrom(), example 3
remaining (sorted): [3, 5]
% missingancestors(), example 1
return [3, 7, 11]
% missingancestors(), example 2
return [5, 10]
% missingancestors(), example 3
return [3, 6, 9, 11]
% removeancestorsfrom(), bigger graph
Ok
% lazy ancestor set for [], stoprev = 0, inclusive = False
membership: []
iteration: []
% lazy ancestor set for [11, 13], stoprev = 0, inclusive = False
membership: [7, 8, 3, 4, 1, 0]
iteration: [8, 7, 4, 3, 2, 1, 0]
% lazy ancestor set for [1, 3], stoprev = 0, inclusive = False
membership: [1, 0]
iteration: [1, 0]
% lazy ancestor set for [11, 13], stoprev = 0, inclusive = True
membership: [11, 13, 7, 8, 3, 4, 1, 0]
iteration: [13, 11, 8, 7, 4, 3, 2, 1, 0]
% lazy ancestor set for [11, 13], stoprev = 6, inclusive = False
membership: [7, 8]
iteration: [8, 7]
% lazy ancestor set for [11, 13], stoprev = 6, inclusive = True
membership: [11, 13, 7, 8]
iteration: [13, 11, 8, 7]
% lazy ancestor set for [11, 13], stoprev = 11, inclusive = True
membership: [11, 13]
iteration: [13, 11]
% lazy ancestor set for [11, 13], stoprev = 12, inclusive = True
membership: [13]
iteration: [13]
% lazy ancestor set for [10, 1], stoprev = 0, inclusive = True
membership: [2, 10, 4, 5, 0, 1]
iteration: [10, 5, 4, 2, 1, 0]