contrib/casesmash.py

testing: allow Hypothesis to enable extensions

This adds support for testing extensions, including both tests
that extensions don't change behaviour and test for specific
commands.

We use the precondition system to determine what commands are
available to us. If we never use any commands enabled by an
extension then that extension is *skippable* and should not
have changed the behaviour of the test. We thus rerun the test
with an environment variable which is designed to turn off the
extension.

import os, __builtin__
from mercurial import util

def lowerwrap(scope, funcname):
    f = getattr(scope, funcname)
    def wrap(fname, *args, **kwargs):
        d, base = os.path.split(fname)
        try:
            files = os.listdir(d or '.')
        except OSError:
            files = []
        if base in files:
            return f(fname, *args, **kwargs)
        for fn in files:
            if fn.lower() == base.lower():
                return f(os.path.join(d, fn), *args, **kwargs)
        return f(fname, *args, **kwargs)
    scope.__dict__[funcname] = wrap

def normcase(path):
    return path.lower()

os.path.normcase = normcase

for f in 'file open'.split():
    lowerwrap(__builtin__, f)

for f in "chmod chown open lstat stat remove unlink".split():
    lowerwrap(os, f)

for f in "exists lexists".split():
    lowerwrap(os.path, f)

lowerwrap(util, 'posixfile')