context: check file exists before getting data from _wrappedctx
overlayworkingctx class is used to do in-memory merging. The data() function of
that class has logic to look for data() in the wrappedctx if the file data in
cache is empty and if the file is dirty. This assumes that if a file is dirty
and cache has empty data for it, it will exists in the _wrappedctx.
However this assumption can be False in case when we are merging a file which is
empty in destination. In these cases, the backup file 'foo.orig' created by our
internal merge algorithms will be empty, however it won't be present in
_wrappedctx. This case will lead us to error like the one this patch is fixing.
Let's only fallback to getting data from wrappedctx if cache has 'None' as data.
Differential Revision: https://phab.mercurial-scm.org/D6308
from __future__ import absolute_import, print_function
import os
import tempfile
from mercurial import (
pycompat,
util,
)
from hgext.fastannotate import error, revmap
if pycompat.ispy3:
xrange = range
def genhsh(i):
return pycompat.bytechr(i) + b'\0' * 19
def gettemppath():
fd, path = tempfile.mkstemp()
os.close(fd)
os.unlink(path)
return path
def ensure(condition):
if not condition:
raise RuntimeError('Unexpected')
def testbasicreadwrite():
path = gettemppath()
rm = revmap.revmap(path)
ensure(rm.maxrev == 0)
for i in xrange(5):
ensure(rm.rev2hsh(i) is None)
ensure(rm.hsh2rev(b'\0' * 20) is None)
paths = [
b'', b'a', None, b'b', b'b', b'c', b'c', None, b'a', b'b', b'a', b'a']
for i in xrange(1, 5):
ensure(rm.append(genhsh(i), sidebranch=(i & 1), path=paths[i]) == i)
ensure(rm.maxrev == 4)
for i in xrange(1, 5):
ensure(rm.hsh2rev(genhsh(i)) == i)
ensure(rm.rev2hsh(i) == genhsh(i))
# re-load and verify
rm.flush()
rm = revmap.revmap(path)
ensure(rm.maxrev == 4)
for i in xrange(1, 5):
ensure(rm.hsh2rev(genhsh(i)) == i)
ensure(rm.rev2hsh(i) == genhsh(i))
ensure(bool(rm.rev2flag(i) & revmap.sidebranchflag) == bool(i & 1))
# append without calling save() explicitly
for i in xrange(5, 12):
ensure(rm.append(genhsh(i), sidebranch=(i & 1), path=paths[i],
flush=True) == i)
# re-load and verify
rm = revmap.revmap(path)
ensure(rm.maxrev == 11)
for i in xrange(1, 12):
ensure(rm.hsh2rev(genhsh(i)) == i)
ensure(rm.rev2hsh(i) == genhsh(i))
ensure(rm.rev2path(i) == paths[i] or paths[i - 1])
ensure(bool(rm.rev2flag(i) & revmap.sidebranchflag) == bool(i & 1))
os.unlink(path)
# missing keys
ensure(rm.rev2hsh(12) is None)
ensure(rm.rev2hsh(0) is None)
ensure(rm.rev2hsh(-1) is None)
ensure(rm.rev2flag(12) is None)
ensure(rm.rev2path(12) is None)
ensure(rm.hsh2rev(b'\1' * 20) is None)
# illformed hash (not 20 bytes)
try:
rm.append(b'\0')
ensure(False)
except Exception:
pass
def testcorruptformat():
path = gettemppath()
# incorrect header
with open(path, 'wb') as f:
f.write(b'NOT A VALID HEADER')
try:
revmap.revmap(path)
ensure(False)
except error.CorruptedFileError:
pass
# rewrite the file
os.unlink(path)
rm = revmap.revmap(path)
rm.append(genhsh(0), flush=True)
rm = revmap.revmap(path)
ensure(rm.maxrev == 1)
# corrupt the file by appending a byte
size = os.stat(path).st_size
with open(path, 'ab') as f:
f.write(b'\xff')
try:
revmap.revmap(path)
ensure(False)
except error.CorruptedFileError:
pass
# corrupt the file by removing the last byte
ensure(size > 0)
with open(path, 'wb') as f:
f.truncate(size - 1)
try:
revmap.revmap(path)
ensure(False)
except error.CorruptedFileError:
pass
os.unlink(path)
def testcopyfrom():
path = gettemppath()
rm = revmap.revmap(path)
for i in xrange(1, 10):
ensure(rm.append(genhsh(i),
sidebranch=(i & 1), path=(b'%d' % (i // 3))) == i)
rm.flush()
# copy rm to rm2
rm2 = revmap.revmap()
rm2.copyfrom(rm)
path2 = gettemppath()
rm2.path = path2
rm2.flush()
# two files should be the same
ensure(len(set(util.readfile(p) for p in [path, path2])) == 1)
os.unlink(path)
os.unlink(path2)
class fakefctx(object):
def __init__(self, node, path=None):
self._node = node
self._path = path
def node(self):
return self._node
def path(self):
return self._path
def testcontains():
path = gettemppath()
rm = revmap.revmap(path)
for i in xrange(1, 5):
ensure(rm.append(genhsh(i), sidebranch=(i & 1)) == i)
for i in xrange(1, 5):
ensure(((genhsh(i), None) in rm) == ((i & 1) == 0))
ensure((fakefctx(genhsh(i)) in rm) == ((i & 1) == 0))
for i in xrange(5, 10):
ensure(fakefctx(genhsh(i)) not in rm)
ensure((genhsh(i), None) not in rm)
# "contains" checks paths
rm = revmap.revmap()
for i in xrange(1, 5):
ensure(rm.append(genhsh(i), path=(b'%d' % (i // 2))) == i)
for i in xrange(1, 5):
ensure(fakefctx(genhsh(i), path=(b'%d' % (i // 2))) in rm)
ensure(fakefctx(genhsh(i), path=b'a') not in rm)
def testlastnode():
path = gettemppath()
ensure(revmap.getlastnode(path) is None)
rm = revmap.revmap(path)
ensure(revmap.getlastnode(path) is None)
for i in xrange(1, 10):
hsh = genhsh(i)
rm.append(hsh, path=(b'%d' % (i // 2)), flush=True)
ensure(revmap.getlastnode(path) == hsh)
rm2 = revmap.revmap(path)
ensure(rm2.rev2hsh(rm2.maxrev) == hsh)
testbasicreadwrite()
testcorruptformat()
testcopyfrom()
testcontains()
testlastnode()