tests: comprehensively test HTTP server permissions checking
We didn't have test coverage for numerous web.* config options. We
add that test coverage.
Included in the tests are tests for custom commands. We have commands
that are supposedly read-only and perform writes and a variation of
each that does and does not define its operation type in
hgweb_mod.perms.
The tests reveal a handful of security bugs related to permissions
checking. Subsequent commits will address these security bugs.
#require execbit
$ hg init repo
$ cd repo
$ echo foo > foo
$ chmod 644 foo
$ hg ci -qAm '644'
$ chmod 755 foo
$ hg ci -qAm '755'
reverting to rev 0
$ hg revert -a -r 0
reverting foo
$ hg st
M foo
$ hg diff --git
diff --git a/foo b/foo
old mode 100755
new mode 100644
$ cd ..