tests/test-extensions-wrapfunction.py
author Pierre-Yves David <pierre-yves.david@octobus.net>
Tue, 06 Jul 2021 16:12:09 +0200
branchstable
changeset 47504 411dc27fd9fd
parent 43076 2372284d9457
child 48875 6000f5b25c9b
permissions -rw-r--r--
corruption: backout changeset 49fd21f32695 (issue6528) inverting the parent is masking copy information leading to bad content being fetched and bad status result. Since 49fd21f32695, exchange can actively swap these parent corrupting existing changesets and triggering the corruption. Data corruption are considered critical so backing this out and doing and unscheduled release seems in order. Differential Revision: https://phab.mercurial-scm.org/D10995

from __future__ import absolute_import, print_function

from mercurial import extensions


def genwrapper(x):
    def f(orig, *args, **kwds):
        return [x] + orig(*args, **kwds)

    f.x = x
    return f


def getid(wrapper):
    return getattr(wrapper, 'x', '-')


wrappers = [genwrapper(i) for i in range(5)]


class dummyclass(object):
    def getstack(self):
        return ['orig']


dummy = dummyclass()


def batchwrap(wrappers):
    for w in wrappers:
        extensions.wrapfunction(dummy, 'getstack', w)
        print('wrap %d: %s' % (getid(w), dummy.getstack()))


def batchunwrap(wrappers):
    for w in wrappers:
        result = None
        try:
            result = extensions.unwrapfunction(dummy, 'getstack', w)
            msg = str(dummy.getstack())
        except (ValueError, IndexError) as e:
            msg = e.__class__.__name__
        print('unwrap %s: %s: %s' % (getid(w), getid(result), msg))


batchwrap(wrappers + [wrappers[0]])
batchunwrap(
    [
        (wrappers[i] if i is not None and i >= 0 else None)
        for i in [3, None, 0, 4, 0, 2, 1, None]
    ]
)

wrap0 = extensions.wrappedfunction(dummy, 'getstack', wrappers[0])
wrap1 = extensions.wrappedfunction(dummy, 'getstack', wrappers[1])

# Use them in a different order from how they were created to check that
# the wrapping happens in __enter__, not in __init__
print('context manager', dummy.getstack())
with wrap1:
    print('context manager', dummy.getstack())
    with wrap0:
        print('context manager', dummy.getstack())
        # Bad programmer forgets to unwrap the function, but the context
        # managers still unwrap their wrappings.
        extensions.wrapfunction(dummy, 'getstack', wrappers[2])
        print('context manager', dummy.getstack())
    print('context manager', dummy.getstack())
print('context manager', dummy.getstack())

# Wrap callable object which has no __name__
class callableobj(object):
    def __call__(self):
        return ['orig']


dummy.cobj = callableobj()
extensions.wrapfunction(dummy, 'cobj', wrappers[0])
print('wrap callable object', dummy.cobj())