match: introduce boolean prefix() method
tl;dr: This is another step towards a (previously unstated) goal of
eliminating match.files() in conditions.
There are four types of matchers:
* always: Matches everything, checked with always(), files() is empty
* exact: Matches exact set of files, checked with isexact(), files()
contains the files to match
* patterns: Matches more complex patterns, checked with anypats(),
files() contains roots of the matched patterns
* prefix: Matches simple 'path:' patterns as prefixes ('foo' matches
both 'foo' and 'foo/bar'), no single method to check, files()
contains the prefixes to match
For completeness, it would be nice to have a method for checking for
the "prefix" type of matcher as well, so let's add that, making it
return True simply when none of the others do.
The larger goal here is to eliminate uses of match.files() in
conditions (i.e. bool(match.files())). The reason for this is that
there are scenarios when you would like to create a "prefix" matcher
that happens to match no files. One example is for 'hg files -I foo
bar'. The narrowmatcher also restricts the set of files given and it
would not surprise me if have bugs caused by that already. Note that
'if m.files() and not m.anypats()' and similar is sometimes used to
catch the "exact" and "prefix" cases above.
# Copyright 2011 Fog Creek Software
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import os
import urllib2
import re
from mercurial import error, httppeer, util, wireproto
from mercurial.i18n import _
import lfutil
LARGEFILES_REQUIRED_MSG = ('\nThis repository uses the largefiles extension.'
'\n\nPlease enable it in your Mercurial config '
'file.\n')
# these will all be replaced by largefiles.uisetup
capabilitiesorig = None
ssholdcallstream = None
httpoldcallstream = None
def putlfile(repo, proto, sha):
'''Put a largefile into a repository's local store and into the
user cache.'''
proto.redirect()
path = lfutil.storepath(repo, sha)
util.makedirs(os.path.dirname(path))
tmpfp = util.atomictempfile(path, createmode=repo.store.createmode)
try:
proto.getfile(tmpfp)
tmpfp._fp.seek(0)
if sha != lfutil.hexsha1(tmpfp._fp):
raise IOError(0, _('largefile contents do not match hash'))
tmpfp.close()
lfutil.linktousercache(repo, sha)
except IOError, e:
repo.ui.warn(_('largefiles: failed to put %s into store: %s\n') %
(sha, e.strerror))
return wireproto.pushres(1)
finally:
tmpfp.discard()
return wireproto.pushres(0)
def getlfile(repo, proto, sha):
'''Retrieve a largefile from the repository-local cache or system
cache.'''
filename = lfutil.findfile(repo, sha)
if not filename:
raise util.Abort(_('requested largefile %s not present in cache') % sha)
f = open(filename, 'rb')
length = os.fstat(f.fileno())[6]
# Since we can't set an HTTP content-length header here, and
# Mercurial core provides no way to give the length of a streamres
# (and reading the entire file into RAM would be ill-advised), we
# just send the length on the first line of the response, like the
# ssh proto does for string responses.
def generator():
yield '%d\n' % length
for chunk in util.filechunkiter(f):
yield chunk
return wireproto.streamres(generator())
def statlfile(repo, proto, sha):
'''Return '2\n' if the largefile is missing, '0\n' if it seems to be in
good condition.
The value 1 is reserved for mismatched checksum, but that is too expensive
to be verified on every stat and must be caught be running 'hg verify'
server side.'''
filename = lfutil.findfile(repo, sha)
if not filename:
return '2\n'
return '0\n'
def wirereposetup(ui, repo):
class lfileswirerepository(repo.__class__):
def putlfile(self, sha, fd):
# unfortunately, httprepository._callpush tries to convert its
# input file-like into a bundle before sending it, so we can't use
# it ...
if issubclass(self.__class__, httppeer.httppeer):
res = None
try:
res = self._call('putlfile', data=fd, sha=sha,
headers={'content-type':'application/mercurial-0.1'})
d, output = res.split('\n', 1)
for l in output.splitlines(True):
self.ui.warn(_('remote: '), l) # assume l ends with \n
return int(d)
except (ValueError, urllib2.HTTPError):
self.ui.warn(_('unexpected putlfile response: %r\n') % res)
return 1
# ... but we can't use sshrepository._call because the data=
# argument won't get sent, and _callpush does exactly what we want
# in this case: send the data straight through
else:
try:
ret, output = self._callpush("putlfile", fd, sha=sha)
if ret == "":
raise error.ResponseError(_('putlfile failed:'),
output)
return int(ret)
except IOError:
return 1
except ValueError:
raise error.ResponseError(
_('putlfile failed (unexpected response):'), ret)
def getlfile(self, sha):
"""returns an iterable with the chunks of the file with sha sha"""
stream = self._callstream("getlfile", sha=sha)
length = stream.readline()
try:
length = int(length)
except ValueError:
self._abort(error.ResponseError(_("unexpected response:"),
length))
# SSH streams will block if reading more than length
for chunk in util.filechunkiter(stream, 128 * 1024, length):
yield chunk
# HTTP streams must hit the end to process the last empty
# chunk of Chunked-Encoding so the connection can be reused.
if issubclass(self.__class__, httppeer.httppeer):
chunk = stream.read(1)
if chunk:
self._abort(error.ResponseError(_("unexpected response:"),
chunk))
@wireproto.batchable
def statlfile(self, sha):
f = wireproto.future()
result = {'sha': sha}
yield result, f
try:
yield int(f.value)
except (ValueError, urllib2.HTTPError):
# If the server returns anything but an integer followed by a
# newline, newline, it's not speaking our language; if we get
# an HTTP error, we can't be sure the largefile is present;
# either way, consider it missing.
yield 2
repo.__class__ = lfileswirerepository
# advertise the largefiles=serve capability
def capabilities(repo, proto):
return capabilitiesorig(repo, proto) + ' largefiles=serve'
def heads(repo, proto):
if lfutil.islfilesrepo(repo):
return wireproto.ooberror(LARGEFILES_REQUIRED_MSG)
return wireproto.heads(repo, proto)
def sshrepocallstream(self, cmd, **args):
if cmd == 'heads' and self.capable('largefiles'):
cmd = 'lheads'
if cmd == 'batch' and self.capable('largefiles'):
args['cmds'] = args['cmds'].replace('heads ', 'lheads ')
return ssholdcallstream(self, cmd, **args)
headsre = re.compile(r'(^|;)heads\b')
def httprepocallstream(self, cmd, **args):
if cmd == 'heads' and self.capable('largefiles'):
cmd = 'lheads'
if cmd == 'batch' and self.capable('largefiles'):
args['cmds'] = headsre.sub('lheads', args['cmds'])
return httpoldcallstream(self, cmd, **args)