context.status: move manifest caching trick to _buildstatus()
In basectx._buildstatus(), we read the manifests for the two revisions
being compared. For "caching reasons" unknown to me, it is better to
read the earlier manifest first, which basectx._prestatus() takes care
of. However, if the 'self' context is a committablectx and the 'other'
context is the parent of the working directory (as in the very common
case of plain "hg status"), there is no need to read any manifests at
all -- all that's needed is the dirstate status. To avoid reading the
manifests, _prestatus() is overridden in committablectx and avoids
calling its super method, and _buildstatus() calls its super method
only if the 'other' context is not the parent of the working
directory.
It seems easier to follow what's happening if we move the pre-fetching
to _buildstatus() just before the place where the manifests are
fetched. We just need to add an extra check that the revision is not
None to handle the case that was previously handled by subclass
overriding. That also makes it safe for committablectx._prestatus() to
call its parent, although the latter now becomes empty, so we won't
bother.
# changelog.py - changelog class for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import weakref
from node import bin, hex, nullid
from i18n import _
import util, error, revlog, encoding
_defaultextra = {'branch': 'default'}
def _string_escape(text):
"""
>>> d = {'nl': chr(10), 'bs': chr(92), 'cr': chr(13), 'nul': chr(0)}
>>> s = "ab%(nl)scd%(bs)s%(bs)sn%(nul)sab%(cr)scd%(bs)s%(nl)s" % d
>>> s
'ab\\ncd\\\\\\\\n\\x00ab\\rcd\\\\\\n'
>>> res = _string_escape(s)
>>> s == res.decode('string_escape')
True
"""
# subset of the string_escape codec
text = text.replace('\\', '\\\\').replace('\n', '\\n').replace('\r', '\\r')
return text.replace('\0', '\\0')
def decodeextra(text):
"""
>>> sorted(decodeextra(encodeextra({'foo': 'bar', 'baz': chr(0) + '2'})
... ).iteritems())
[('baz', '\\x002'), ('branch', 'default'), ('foo', 'bar')]
>>> sorted(decodeextra(encodeextra({'foo': 'bar',
... 'baz': chr(92) + chr(0) + '2'})
... ).iteritems())
[('baz', '\\\\\\x002'), ('branch', 'default'), ('foo', 'bar')]
"""
extra = _defaultextra.copy()
for l in text.split('\0'):
if l:
if '\\0' in l:
# fix up \0 without getting into trouble with \\0
l = l.replace('\\\\', '\\\\\n')
l = l.replace('\\0', '\0')
l = l.replace('\n', '')
k, v = l.decode('string_escape').split(':', 1)
extra[k] = v
return extra
def encodeextra(d):
# keys must be sorted to produce a deterministic changelog entry
items = [_string_escape('%s:%s' % (k, d[k])) for k in sorted(d)]
return "\0".join(items)
def stripdesc(desc):
"""strip trailing whitespace and leading and trailing empty lines"""
return '\n'.join([l.rstrip() for l in desc.splitlines()]).strip('\n')
class appender(object):
'''the changelog index must be updated last on disk, so we use this class
to delay writes to it'''
def __init__(self, vfs, name, mode, buf):
self.data = buf
fp = vfs(name, mode)
self.fp = fp
self.offset = fp.tell()
self.size = vfs.fstat(fp).st_size
def end(self):
return self.size + len("".join(self.data))
def tell(self):
return self.offset
def flush(self):
pass
def close(self):
self.fp.close()
def seek(self, offset, whence=0):
'''virtual file offset spans real file and data'''
if whence == 0:
self.offset = offset
elif whence == 1:
self.offset += offset
elif whence == 2:
self.offset = self.end() + offset
if self.offset < self.size:
self.fp.seek(self.offset)
def read(self, count=-1):
'''only trick here is reads that span real file and data'''
ret = ""
if self.offset < self.size:
s = self.fp.read(count)
ret = s
self.offset += len(s)
if count > 0:
count -= len(s)
if count != 0:
doff = self.offset - self.size
self.data.insert(0, "".join(self.data))
del self.data[1:]
s = self.data[0][doff:doff + count]
self.offset += len(s)
ret += s
return ret
def write(self, s):
self.data.append(str(s))
self.offset += len(s)
def _divertopener(opener, target):
"""build an opener that writes in 'target.a' instead of 'target'"""
def _divert(name, mode='r'):
if name != target:
return opener(name, mode)
return opener(name + ".a", mode)
return _divert
def _delayopener(opener, target, buf):
"""build an opener that stores chunks in 'buf' instead of 'target'"""
def _delay(name, mode='r'):
if name != target:
return opener(name, mode)
return appender(opener, name, mode, buf)
return _delay
class changelog(revlog.revlog):
def __init__(self, opener):
revlog.revlog.__init__(self, opener, "00changelog.i")
if self._initempty:
# changelogs don't benefit from generaldelta
self.version &= ~revlog.REVLOGGENERALDELTA
self._generaldelta = False
self._realopener = opener
self._delayed = False
self._delaybuf = None
self._divert = False
self.filteredrevs = frozenset()
def tip(self):
"""filtered version of revlog.tip"""
for i in xrange(len(self) -1, -2, -1):
if i not in self.filteredrevs:
return self.node(i)
def __iter__(self):
"""filtered version of revlog.__iter__"""
if len(self.filteredrevs) == 0:
return revlog.revlog.__iter__(self)
def filterediter():
for i in xrange(len(self)):
if i not in self.filteredrevs:
yield i
return filterediter()
def revs(self, start=0, stop=None):
"""filtered version of revlog.revs"""
for i in super(changelog, self).revs(start, stop):
if i not in self.filteredrevs:
yield i
@util.propertycache
def nodemap(self):
# XXX need filtering too
self.rev(self.node(0))
return self._nodecache
def hasnode(self, node):
"""filtered version of revlog.hasnode"""
try:
i = self.rev(node)
return i not in self.filteredrevs
except KeyError:
return False
def headrevs(self):
if self.filteredrevs:
try:
return self.index.headrevsfiltered(self.filteredrevs)
# AttributeError covers non-c-extension environments and
# old c extensions without filter handling.
except AttributeError:
return self._headrevs()
return super(changelog, self).headrevs()
def strip(self, *args, **kwargs):
# XXX make something better than assert
# We can't expect proper strip behavior if we are filtered.
assert not self.filteredrevs
super(changelog, self).strip(*args, **kwargs)
def rev(self, node):
"""filtered version of revlog.rev"""
r = super(changelog, self).rev(node)
if r in self.filteredrevs:
raise error.FilteredLookupError(hex(node), self.indexfile,
_('filtered node'))
return r
def node(self, rev):
"""filtered version of revlog.node"""
if rev in self.filteredrevs:
raise error.FilteredIndexError(rev)
return super(changelog, self).node(rev)
def linkrev(self, rev):
"""filtered version of revlog.linkrev"""
if rev in self.filteredrevs:
raise error.FilteredIndexError(rev)
return super(changelog, self).linkrev(rev)
def parentrevs(self, rev):
"""filtered version of revlog.parentrevs"""
if rev in self.filteredrevs:
raise error.FilteredIndexError(rev)
return super(changelog, self).parentrevs(rev)
def flags(self, rev):
"""filtered version of revlog.flags"""
if rev in self.filteredrevs:
raise error.FilteredIndexError(rev)
return super(changelog, self).flags(rev)
def delayupdate(self, tr):
"delay visibility of index updates to other readers"
if not self._delayed:
if len(self) == 0:
self._divert = True
if self._realopener.exists(self.indexfile + '.a'):
self._realopener.unlink(self.indexfile + '.a')
self.opener = _divertopener(self._realopener, self.indexfile)
else:
self._delaybuf = []
self.opener = _delayopener(self._realopener, self.indexfile,
self._delaybuf)
self._delayed = True
tr.addpending('cl-%i' % id(self), self._writepending)
trp = weakref.proxy(tr)
tr.addfinalize('cl-%i' % id(self), lambda: self._finalize(trp))
def _finalize(self, tr):
"finalize index updates"
self._delayed = False
self.opener = self._realopener
# move redirected index data back into place
if self._divert:
assert not self._delaybuf
tmpname = self.indexfile + ".a"
nfile = self.opener.open(tmpname)
nfile.close()
self.opener.rename(tmpname, self.indexfile)
elif self._delaybuf:
fp = self.opener(self.indexfile, 'a')
fp.write("".join(self._delaybuf))
fp.close()
self._delaybuf = None
self._divert = False
# split when we're done
self.checkinlinesize(tr)
def readpending(self, file):
r = revlog.revlog(self.opener, file)
self.index = r.index
self.nodemap = r.nodemap
self._nodecache = r._nodecache
self._chunkcache = r._chunkcache
def _writepending(self):
"create a file containing the unfinalized state for pretxnchangegroup"
if self._delaybuf:
# make a temporary copy of the index
fp1 = self._realopener(self.indexfile)
fp2 = self._realopener(self.indexfile + ".a", "w")
fp2.write(fp1.read())
# add pending data
fp2.write("".join(self._delaybuf))
fp2.close()
# switch modes so finalize can simply rename
self._delaybuf = None
self._divert = True
self.opener = _divertopener(self._realopener, self.indexfile)
if self._divert:
return True
return False
def checkinlinesize(self, tr, fp=None):
if not self._delayed:
revlog.revlog.checkinlinesize(self, tr, fp)
def read(self, node):
"""
format used:
nodeid\n : manifest node in ascii
user\n : user, no \n or \r allowed
time tz extra\n : date (time is int or float, timezone is int)
: extra is metadata, encoded and separated by '\0'
: older versions ignore it
files\n\n : files modified by the cset, no \n or \r allowed
(.*) : comment (free text, ideally utf-8)
changelog v0 doesn't use extra
"""
text = self.revision(node)
if not text:
return (nullid, "", (0, 0), [], "", _defaultextra)
last = text.index("\n\n")
desc = encoding.tolocal(text[last + 2:])
l = text[:last].split('\n')
manifest = bin(l[0])
user = encoding.tolocal(l[1])
tdata = l[2].split(' ', 2)
if len(tdata) != 3:
time = float(tdata[0])
try:
# various tools did silly things with the time zone field.
timezone = int(tdata[1])
except ValueError:
timezone = 0
extra = _defaultextra
else:
time, timezone = float(tdata[0]), int(tdata[1])
extra = decodeextra(tdata[2])
files = l[3:]
return (manifest, user, (time, timezone), files, desc, extra)
def add(self, manifest, files, desc, transaction, p1, p2,
user, date=None, extra=None):
# Convert to UTF-8 encoded bytestrings as the very first
# thing: calling any method on a localstr object will turn it
# into a str object and the cached UTF-8 string is thus lost.
user, desc = encoding.fromlocal(user), encoding.fromlocal(desc)
user = user.strip()
# An empty username or a username with a "\n" will make the
# revision text contain two "\n\n" sequences -> corrupt
# repository since read cannot unpack the revision.
if not user:
raise error.RevlogError(_("empty username"))
if "\n" in user:
raise error.RevlogError(_("username %s contains a newline")
% repr(user))
desc = stripdesc(desc)
if date:
parseddate = "%d %d" % util.parsedate(date)
else:
parseddate = "%d %d" % util.makedate()
if extra:
branch = extra.get("branch")
if branch in ("default", ""):
del extra["branch"]
elif branch in (".", "null", "tip"):
raise error.RevlogError(_('the name \'%s\' is reserved')
% branch)
if extra:
extra = encodeextra(extra)
parseddate = "%s %s" % (parseddate, extra)
l = [hex(manifest), user, parseddate] + sorted(files) + ["", desc]
text = "\n".join(l)
return self.addrevision(text, transaction, len(self), p1, p2)
def branchinfo(self, rev):
"""return the branch name and open/close state of a revision
This function exists because creating a changectx object
just to access this is costly."""
extra = self.read(rev)[5]
return encoding.tolocal(extra.get("branch")), 'close' in extra