sshpeer: make pipe polling code more explicit
"hasbuffer" is a property on our special bufferedinputpipe class.
When reading this code, I thought it might have had something
special to do properties on built-in types. But "hasbuffer" doesn't
appear in the CPython code base for either 2.7 or 3.7, so the
answer is no.
Let's make the code more explicit about the fact that it deals with
our special bufferedinputpipe type.
Differential Revision: https://phab.mercurial-scm.org/D2382
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 >= 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())