dirstate-v2: no longer register the data-file during transaction
If the data file change during the transaction, we cannot truncate it.
The content of the file itself is fine as it will get backed up at the same time
as the docket.
Leaving the trailing data at the end of failed transaction is fine. The
dirstate-v2 format supports it. The dead data will simply we written over if
necessary.
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:
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:
def __call__(self):
return ['orig']
dummy.cobj = callableobj()
extensions.wrapfunction(dummy, 'cobj', wrappers[0])
print('wrap callable object', dummy.cobj())