windows: gracefully handle when the username cannot be determined
This assumes implementation details, but I don't see any other way than to check
the environment variables ourselves (which would miss out on any future
enhancements that Python may make). This was originally reported as
https://foss.heptapod.net/mercurial/tortoisehg/thg/-/issues/5835.
#require execbit
$ rm -rf a
$ hg init a
$ cd a
$ echo foo > foo
$ hg ci -qAm0
$ echo toremove > toremove
$ echo todelete > todelete
$ chmod +x foo toremove todelete
$ hg ci -qAm1
Test that local removed/deleted, remote removed works with flags
$ hg rm toremove
$ rm todelete
$ hg co -q 0
$ echo dirty > foo
$ hg up -c
abort: uncommitted changes
[20]
$ hg up -q
$ cat foo
dirty
$ hg st -A
M foo
C todelete
C toremove
Validate update of standalone execute bit change:
$ hg up -C 0
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ chmod -x foo
$ hg ci -m removeexec
nothing changed
[1]
$ hg up -C 0
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg up
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
$ cd ..