perf: ensure HGRCPATH is exported on Windows
After dropping the garbage collector hack, `hg perfstartup` started yelling
about not being able to import the evolve extension, which I have in my user
config. Launching `env` shows that an empty HGRCPATH isn't exported to the
environment. Since `env` doesn't quote, I have no idea if the variable is
trimmed, but Mercurial doesn't complain when processing it.
#require test-repo execbit
$ . "$TESTDIR/helpers-testrepo.sh"
$ cd "`dirname "$TESTDIR"`"
look for python scripts without the execute bit
$ hg files 'set:**.py and not exec() and grep(r"^#!.*?python")'
[1]
look for python scripts with execute bit but not shebang
$ hg files 'set:**.py and exec() and not grep(r"^#!.*?python")'
[1]
look for shell scripts with execute bit but not shebang
$ hg files 'set:**.sh and exec() and not grep(r"^#!.*(ba)?sh")'
[1]
look for non scripts with no shebang
$ hg files 'set:exec() and not **.sh and not **.py and not grep(r"^#!")'
[1]