cleanup: polyfill assertRaisesRegex so we can avoid assertRaisesRegexp
The latter is deprecated on Python 3.7 and causes our tests to fail
due to the warning.
Differential Revision: https://phab.mercurial-scm.org/D3375
#require test-repo execbit
$ . "$TESTDIR/helpers-testrepo.sh"
$ cd "`dirname "$TESTDIR"`"
look for python scripts without the execute bit
$ testrepohg files 'set:**.py and not exec() and grep(r"^#!.*?python")'
[1]
look for python scripts with execute bit but not shebang
$ testrepohg files 'set:**.py and exec() and not grep(r"^#!.*?python")'
[1]
look for shell scripts with execute bit but not shebang
$ testrepohg files 'set:**.sh and exec() and not grep(r"^#!.*(ba)?sh")'
[1]
look for non scripts with no shebang
$ testrepohg files 'set:exec() and not **.sh and not **.py and not grep(r"^#!")'
[1]