tests/test-extensions-wrapfunction.py

streamclone: treat volatile file as "fullfile"

The nodemap related file might change (or get deleted) during the stream clone
in a way incompatible with the streaming process.

So we introduce a new flag for this type of file and integrate it with the
existing `revlog_type` field recently added to `store.walk` returns.

We use that new flat to dispatch such file to the existing mechanism for "atomic
replacement" file for the nodemap docket and datafile. This fix the bugs we have
been adding tests for.

Strictly speaking, the nodemap datafile is happened only a could maybe be used
in a slightly more efficient way, however this is good enough for now.

Differential Revision: https://phab.mercurial-scm.org/D10481

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())