tests: add tests and document expectations from visit_children_set in rust
The tests this patch are adding have the form of formal spec in
invariants::visit_children_set::holds,
and then a series of checks that all examples must satisfy this
formal spec.
I tried to make the spec consistent with how this function is used
and how it was originally conceived. This is in conflict with how it's
documented in Rust. Some of the implementations also fail to implement
this spec, which leads to bugs, in particular when complicated patterns
are used with `hg status`.
# Test the config layer generated by environment variables
import os
from mercurial import (
encoding,
extensions,
rcutil,
ui as uimod,
util,
)
from mercurial.utils import procutil
testtmp = encoding.environ[b'TESTTMP']
# prepare hgrc files
def join(name):
return os.path.join(testtmp, name)
with open(join(b'sysrc'), 'wb') as f:
f.write(b'[ui]\neditor=e0\n[pager]\npager=p0\n')
with open(join(b'userrc'), 'wb') as f:
f.write(b'[ui]\neditor=e1')
# replace rcpath functions so they point to the files above
def systemrcpath():
return [join(b'sysrc')]
def userrcpath():
return [join(b'userrc')]
extensions.wrapfunction(rcutil, 'default_rc_resources', lambda orig: [])
rcutil.systemrcpath = systemrcpath
rcutil.userrcpath = userrcpath
# utility to print configs
def printconfigs(env):
encoding.environ = env
rcutil._rccomponents = None # reset cache
ui = uimod.ui.load()
for section, name, value in ui.walkconfig():
source = ui.configsource(section, name)
procutil.stdout.write(
b'%s.%s=%s # %s\n' % (section, name, value, util.pconvert(source))
)
procutil.stdout.write(b'\n')
# environment variable overrides
printconfigs({})
printconfigs({b'EDITOR': b'e2', b'PAGER': b'p2'})