Mercurial > hg
view hgext/eol.py @ 32697:19b9fc40cc51
revlog: skeleton support for version 2 revlogs
There are a number of improvements we want to make to revlogs
that will require a new version - version 2. It is unclear what the
full set of improvements will be or when we'll be done with them.
What I do know is that the process will likely take longer than a
single release, will require input from various stakeholders to
evaluate changes, and will have many contentious debates and
bikeshedding.
It is unrealistic to develop revlog version 2 up front: there
are just too many uncertainties that we won't know until things
are implemented and experiments are run. Some changes will also
be invasive and prone to bit rot, so sitting on dozens of patches
is not practical.
This commit introduces skeleton support for version 2 revlogs in
a way that is flexible and not bound by backwards compatibility
concerns.
An experimental repo requirement for denoting revlog v2 has been
added. The requirement string has a sub-version component to it.
This will allow us to declare multiple requirements in the course
of developing revlog v2. Whenever we change the in-development
revlog v2 format, we can tweak the string, creating a new
requirement and locking out old clients. This will allow us to
make as many backwards incompatible changes and experiments to
revlog v2 as we want. In other words, we can land code and make
meaningful progress towards revlog v2 while still maintaining
extreme format flexibility up until the point we freeze the
format and remove the experimental labels.
To enable the new repo requirement, you must supply an experimental
and undocumented config option. But not just any boolean flag
will do: you need to explicitly use a value that no sane person
should ever type. This is an additional guard against enabling
revlog v2 on an installation it shouldn't be enabled on. The
specific scenario I'm trying to prevent is say a user with a
4.4 client with a frozen format enabling the option but then
downgrading to 4.3 and accidentally creating repos with an
outdated and unsupported repo format. Requiring a "challenge"
string should prevent this.
Because the format is not yet finalized and I don't want to take
any chances, revlog v2's version is currently 0xDEAD. I figure
squatting on a value we're likely never to use as an actual revlog
version to mean "internal testing only" is acceptable. And
"dead" is easily recognized as something meaningful.
There is a bunch of cleanup that is needed before work on revlog
v2 begins in earnest. I plan on doing that work once this patch
is accepted and we're comfortable with the idea of starting down
this path.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 19 May 2017 20:29:11 -0700 |
parents | fe9b33bcec6a |
children | 74930cf4a10e |
line wrap: on
line source
"""automatically manage newlines in repository files This extension allows you to manage the type of line endings (CRLF or LF) that are used in the repository and in the local working directory. That way you can get CRLF line endings on Windows and LF on Unix/Mac, thereby letting everybody use their OS native line endings. The extension reads its configuration from a versioned ``.hgeol`` configuration file found in the root of the working directory. The ``.hgeol`` file use the same syntax as all other Mercurial configuration files. It uses two sections, ``[patterns]`` and ``[repository]``. The ``[patterns]`` section specifies how line endings should be converted between the working directory and the repository. The format is specified by a file pattern. The first match is used, so put more specific patterns first. The available line endings are ``LF``, ``CRLF``, and ``BIN``. Files with the declared format of ``CRLF`` or ``LF`` are always checked out and stored in the repository in that format and files declared to be binary (``BIN``) are left unchanged. Additionally, ``native`` is an alias for checking out in the platform's default line ending: ``LF`` on Unix (including Mac OS X) and ``CRLF`` on Windows. Note that ``BIN`` (do nothing to line endings) is Mercurial's default behavior; it is only needed if you need to override a later, more general pattern. The optional ``[repository]`` section specifies the line endings to use for files stored in the repository. It has a single setting, ``native``, which determines the storage line endings for files declared as ``native`` in the ``[patterns]`` section. It can be set to ``LF`` or ``CRLF``. The default is ``LF``. For example, this means that on Windows, files configured as ``native`` (``CRLF`` by default) will be converted to ``LF`` when stored in the repository. Files declared as ``LF``, ``CRLF``, or ``BIN`` in the ``[patterns]`` section are always stored as-is in the repository. Example versioned ``.hgeol`` file:: [patterns] **.py = native **.vcproj = CRLF **.txt = native Makefile = LF **.jpg = BIN [repository] native = LF .. note:: The rules will first apply when files are touched in the working directory, e.g. by updating to null and back to tip to touch all files. The extension uses an optional ``[eol]`` section read from both the normal Mercurial configuration files and the ``.hgeol`` file, with the latter overriding the former. You can use that section to control the overall behavior. There are three settings: - ``eol.native`` (default ``os.linesep``) can be set to ``LF`` or ``CRLF`` to override the default interpretation of ``native`` for checkout. This can be used with :hg:`archive` on Unix, say, to generate an archive where files have line endings for Windows. - ``eol.only-consistent`` (default True) can be set to False to make the extension convert files with inconsistent EOLs. Inconsistent means that there is both ``CRLF`` and ``LF`` present in the file. Such files are normally not touched under the assumption that they have mixed EOLs on purpose. - ``eol.fix-trailing-newline`` (default False) can be set to True to ensure that converted files end with a EOL character (either ``\\n`` or ``\\r\\n`` as per the configured patterns). The extension provides ``cleverencode:`` and ``cleverdecode:`` filters like the deprecated win32text extension does. This means that you can disable win32text and enable eol and your filters will still work. You only need to these filters until you have prepared a ``.hgeol`` file. The ``win32text.forbid*`` hooks provided by the win32text extension have been unified into a single hook named ``eol.checkheadshook``. The hook will lookup the expected line endings from the ``.hgeol`` file, which means you must migrate to a ``.hgeol`` file first before using the hook. ``eol.checkheadshook`` only checks heads, intermediate invalid revisions will be pushed. To forbid them completely, use the ``eol.checkallhook`` hook. These hooks are best used as ``pretxnchangegroup`` hooks. See :hg:`help patterns` for more information about the glob patterns used. """ from __future__ import absolute_import import os import re from mercurial.i18n import _ from mercurial import ( config, error, extensions, match, pycompat, util, ) # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should # be specifying the version(s) of Mercurial they are tested with, or # leave the attribute unspecified. testedwith = 'ships-with-hg-core' # Matches a lone LF, i.e., one that is not part of CRLF. singlelf = re.compile('(^|[^\r])\n') def inconsistenteol(data): return '\r\n' in data and singlelf.search(data) def tolf(s, params, ui, **kwargs): """Filter to convert to LF EOLs.""" if util.binary(s): return s if ui.configbool('eol', 'only-consistent', True) and inconsistenteol(s): return s if (ui.configbool('eol', 'fix-trailing-newline', False) and s and s[-1] != '\n'): s = s + '\n' return util.tolf(s) def tocrlf(s, params, ui, **kwargs): """Filter to convert to CRLF EOLs.""" if util.binary(s): return s if ui.configbool('eol', 'only-consistent', True) and inconsistenteol(s): return s if (ui.configbool('eol', 'fix-trailing-newline', False) and s and s[-1] != '\n'): s = s + '\n' return util.tocrlf(s) def isbinary(s, params): """Filter to do nothing with the file.""" return s filters = { 'to-lf': tolf, 'to-crlf': tocrlf, 'is-binary': isbinary, # The following provide backwards compatibility with win32text 'cleverencode:': tolf, 'cleverdecode:': tocrlf } class eolfile(object): def __init__(self, ui, root, data): self._decode = {'LF': 'to-lf', 'CRLF': 'to-crlf', 'BIN': 'is-binary'} self._encode = {'LF': 'to-lf', 'CRLF': 'to-crlf', 'BIN': 'is-binary'} self.cfg = config.config() # Our files should not be touched. The pattern must be # inserted first override a '** = native' pattern. self.cfg.set('patterns', '.hg*', 'BIN', 'eol') # We can then parse the user's patterns. self.cfg.parse('.hgeol', data) isrepolf = self.cfg.get('repository', 'native') != 'CRLF' self._encode['NATIVE'] = isrepolf and 'to-lf' or 'to-crlf' iswdlf = ui.config('eol', 'native', pycompat.oslinesep) in ('LF', '\n') self._decode['NATIVE'] = iswdlf and 'to-lf' or 'to-crlf' include = [] exclude = [] self.patterns = [] for pattern, style in self.cfg.items('patterns'): key = style.upper() if key == 'BIN': exclude.append(pattern) else: include.append(pattern) m = match.match(root, '', [pattern]) self.patterns.append((pattern, key, m)) # This will match the files for which we need to care # about inconsistent newlines. self.match = match.match(root, '', [], include, exclude) def copytoui(self, ui): for pattern, key, m in self.patterns: try: ui.setconfig('decode', pattern, self._decode[key], 'eol') ui.setconfig('encode', pattern, self._encode[key], 'eol') except KeyError: ui.warn(_("ignoring unknown EOL style '%s' from %s\n") % (key, self.cfg.source('patterns', pattern))) # eol.only-consistent can be specified in ~/.hgrc or .hgeol for k, v in self.cfg.items('eol'): ui.setconfig('eol', k, v, 'eol') def checkrev(self, repo, ctx, files): failed = [] for f in (files or ctx.files()): if f not in ctx: continue for pattern, key, m in self.patterns: if not m(f): continue target = self._encode[key] data = ctx[f].data() if (target == "to-lf" and "\r\n" in data or target == "to-crlf" and singlelf.search(data)): failed.append((f, target, str(ctx))) break return failed def parseeol(ui, repo, nodes): try: for node in nodes: try: if node is None: # Cannot use workingctx.data() since it would load # and cache the filters before we configure them. data = repo.wvfs('.hgeol').read() else: data = repo[node]['.hgeol'].data() return eolfile(ui, repo.root, data) except (IOError, LookupError): pass except error.ParseError as inst: ui.warn(_("warning: ignoring .hgeol file due to parse error " "at %s: %s\n") % (inst.args[1], inst.args[0])) return None def _checkhook(ui, repo, node, headsonly): # Get revisions to check and touched files at the same time files = set() revs = set() for rev in xrange(repo[node].rev(), len(repo)): revs.add(rev) if headsonly: ctx = repo[rev] files.update(ctx.files()) for pctx in ctx.parents(): revs.discard(pctx.rev()) failed = [] for rev in revs: ctx = repo[rev] eol = parseeol(ui, repo, [ctx.node()]) if eol: failed.extend(eol.checkrev(repo, ctx, files)) if failed: eols = {'to-lf': 'CRLF', 'to-crlf': 'LF'} msgs = [] for f, target, node in sorted(failed): msgs.append(_(" %s in %s should not have %s line endings") % (f, node, eols[target])) raise error.Abort(_("end-of-line check failed:\n") + "\n".join(msgs)) def checkallhook(ui, repo, node, hooktype, **kwargs): """verify that files have expected EOLs""" _checkhook(ui, repo, node, False) def checkheadshook(ui, repo, node, hooktype, **kwargs): """verify that files have expected EOLs""" _checkhook(ui, repo, node, True) # "checkheadshook" used to be called "hook" hook = checkheadshook def preupdate(ui, repo, hooktype, parent1, parent2): repo.loadeol([parent1]) return False def uisetup(ui): ui.setconfig('hooks', 'preupdate.eol', preupdate, 'eol') def extsetup(ui): try: extensions.find('win32text') ui.warn(_("the eol extension is incompatible with the " "win32text extension\n")) except KeyError: pass def reposetup(ui, repo): uisetup(repo.ui) if not repo.local(): return for name, fn in filters.iteritems(): repo.adddatafilter(name, fn) ui.setconfig('patch', 'eol', 'auto', 'eol') class eolrepo(repo.__class__): def loadeol(self, nodes): eol = parseeol(self.ui, self, nodes) if eol is None: return None eol.copytoui(self.ui) return eol.match def _hgcleardirstate(self): self._eolmatch = self.loadeol([None, 'tip']) if not self._eolmatch: self._eolmatch = util.never return oldeol = None try: cachemtime = os.path.getmtime(self.vfs.join("eol.cache")) except OSError: cachemtime = 0 else: olddata = self.vfs.read("eol.cache") if olddata: oldeol = eolfile(self.ui, self.root, olddata) try: eolmtime = os.path.getmtime(self.wjoin(".hgeol")) except OSError: eolmtime = 0 if eolmtime > cachemtime: self.ui.debug("eol: detected change in .hgeol\n") hgeoldata = self.wvfs.read('.hgeol') neweol = eolfile(self.ui, self.root, hgeoldata) wlock = None try: wlock = self.wlock() for f in self.dirstate: if self.dirstate[f] != 'n': continue if oldeol is not None: if not oldeol.match(f) and not neweol.match(f): continue oldkey = None for pattern, key, m in oldeol.patterns: if m(f): oldkey = key break newkey = None for pattern, key, m in neweol.patterns: if m(f): newkey = key break if oldkey == newkey: continue # all normal files need to be looked at again since # the new .hgeol file specify a different filter self.dirstate.normallookup(f) # Write the cache to update mtime and cache .hgeol with self.vfs("eol.cache", "w") as f: f.write(hgeoldata) except error.LockUnavailable: # If we cannot lock the repository and clear the # dirstate, then a commit might not see all files # as modified. But if we cannot lock the # repository, then we can also not make a commit, # so ignore the error. pass finally: if wlock is not None: wlock.release() def commitctx(self, ctx, haserror=False): for f in sorted(ctx.added() + ctx.modified()): if not self._eolmatch(f): continue fctx = ctx[f] if fctx is None: continue data = fctx.data() if util.binary(data): # We should not abort here, since the user should # be able to say "** = native" to automatically # have all non-binary files taken care of. continue if inconsistenteol(data): raise error.Abort(_("inconsistent newline style " "in %s\n") % f) return super(eolrepo, self).commitctx(ctx, haserror) repo.__class__ = eolrepo repo._hgcleardirstate()