view hgext/win32text.py @ 35218:d61f2a3d5e53

hgweb: only include graph-related data in jsdata variable on /graph pages (BC)

Historically, client-side graph code was not only rendering the graph itself,
but it was also adding all of the changeset information to the page as well.
It meant that JavaScript code needed to construct valid HTML as a string
(although proper escaping was done server-side). It wasn't too clunky, even
though it meant that a lot of server-side things were duplicated client-side
for no good reason, but the worst thing about it was the data format it used.
It was somewhat future-proof, but not human-friendly, because it was just a
tuple: it was possible to append things to it (as was done in e.g.
270f57d35525), but you'd then have to remember the indices and reading the
resulting JS code wasn't easy, because cur[8] is not descriptive at all.

So what would need to happen for graph to have more features, such as more
changeset information or a different vertex style (branch-closing, obsolete)?
First you'd need to take some property, process it (e.g. escape and pass
through templatefilters function, and mind the encoding too), append it to
jsdata and remember its index, then go add nearly identical JavaScript code to
4 different hgweb themes that use jsdata to render HTML, and finally try and
forget how brittle it all felt. Oh yeah, and the indices go to double digits if
we add 2 more items, say phase and obsolescence, and there are more to come.
Rendering vertex in a different style would need another property (say,
character "o", "_", or "x"), except if you want to be backwards-compatible, it
would need to go after tags and bookmarks, and that just doesn't feel right.

So here I'm trying to fix both the duplication of code and the data format:

- changesets will be rendered by hgweb templates the same way as changelog and
  other such pages, so jsdata won't need any information that's not needed for
  rendering the graph itself

- jsdata will be a dict, or an Object in JS, which is a lot nicer to humans and
  is a lot more future-proof in the long run, because it doesn't use numeric
  indices

What about hgweb themes? Obviously, this will break all hgweb themes that
render graph in JavaScript, including 3rd-party custom ones. But this will also
reduce the size of client-side code and make it more uniform, so that it can be
shared across hgweb themes, further reducing its size. The next few patches
demonstrate that it's not hard to adapt a theme to these changes. And in a
later series, I'm planning to move duplicate JS code from */graph.tmpl to
mercurial.js and leave only 4 lines of code embedded in those <script>
elements, and even that would be just to allow redefining graph.vertex
function. So adapting a custom 3rd-party theme to these changes would mean:

- creating or copying graphnode.tmpl and adding it to the map file (if a theme
  doesn't already use __base__)

- modifying one line in graph.tmpl and simply removing the bigger part of
  JavaScript code from there

Making these changes in this patch and not updating every hgweb theme that uses
jsdata at the same time is a bit of a cheat to make this series more
manageable: /graph pages that use jsdata are broken by this patch, but since
there are no tests that would detect this, bisect works fine; and themes are
updated separately, in the next 4 patches of this series to ease reviewing.

# win32text.py - LF <-> CRLF/CR translation utilities for Windows/Mac users
#
#  Copyright 2005, 2007-2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''perform automatic newline conversion (DEPRECATED)

  Deprecation: The win32text extension requires each user to configure
  the extension again and again for each clone since the configuration
  is not copied when cloning.

  We have therefore made the ``eol`` as an alternative. The ``eol``
  uses a version controlled file for its configuration and each clone
  will therefore use the right settings from the start.

To perform automatic newline conversion, use::

  [extensions]
  win32text =
  [encode]
  ** = cleverencode:
  # or ** = macencode:

  [decode]
  ** = cleverdecode:
  # or ** = macdecode:

If not doing conversion, to make sure you do not commit CRLF/CR by accident::

  [hooks]
  pretxncommit.crlf = python:hgext.win32text.forbidcrlf
  # or pretxncommit.cr = python:hgext.win32text.forbidcr

To do the same check on a server to prevent CRLF/CR from being
pushed or pulled::

  [hooks]
  pretxnchangegroup.crlf = python:hgext.win32text.forbidcrlf
  # or pretxnchangegroup.cr = python:hgext.win32text.forbidcr
'''

from __future__ import absolute_import

import re
from mercurial.i18n import _
from mercurial.node import (
    short,
)
from mercurial import (
    registrar,
    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'

configtable = {}
configitem = registrar.configitem(configtable)

configitem('win32text', 'warn',
    default=True,
)

# regexp for single LF without CR preceding.
re_single_lf = re.compile('(^|[^\r])\n', re.MULTILINE)

newlinestr = {'\r\n': 'CRLF', '\r': 'CR'}
filterstr = {'\r\n': 'clever', '\r': 'mac'}

def checknewline(s, newline, ui=None, repo=None, filename=None):
    # warn if already has 'newline' in repository.
    # it might cause unexpected eol conversion.
    # see issue 302:
    #   https://bz.mercurial-scm.org/302
    if newline in s and ui and filename and repo:
        ui.warn(_('WARNING: %s already has %s line endings\n'
                  'and does not need EOL conversion by the win32text plugin.\n'
                  'Before your next commit, please reconsider your '
                  'encode/decode settings in \nMercurial.ini or %s.\n') %
                (filename, newlinestr[newline], repo.vfs.join('hgrc')))

def dumbdecode(s, cmd, **kwargs):
    checknewline(s, '\r\n', **kwargs)
    # replace single LF to CRLF
    return re_single_lf.sub('\\1\r\n', s)

def dumbencode(s, cmd):
    return s.replace('\r\n', '\n')

def macdumbdecode(s, cmd, **kwargs):
    checknewline(s, '\r', **kwargs)
    return s.replace('\n', '\r')

def macdumbencode(s, cmd):
    return s.replace('\r', '\n')

def cleverdecode(s, cmd, **kwargs):
    if not util.binary(s):
        return dumbdecode(s, cmd, **kwargs)
    return s

def cleverencode(s, cmd):
    if not util.binary(s):
        return dumbencode(s, cmd)
    return s

def macdecode(s, cmd, **kwargs):
    if not util.binary(s):
        return macdumbdecode(s, cmd, **kwargs)
    return s

def macencode(s, cmd):
    if not util.binary(s):
        return macdumbencode(s, cmd)
    return s

_filters = {
    'dumbdecode:': dumbdecode,
    'dumbencode:': dumbencode,
    'cleverdecode:': cleverdecode,
    'cleverencode:': cleverencode,
    'macdumbdecode:': macdumbdecode,
    'macdumbencode:': macdumbencode,
    'macdecode:': macdecode,
    'macencode:': macencode,
    }

def forbidnewline(ui, repo, hooktype, node, newline, **kwargs):
    halt = False
    seen = set()
    # we try to walk changesets in reverse order from newest to
    # oldest, so that if we see a file multiple times, we take the
    # newest version as canonical. this prevents us from blocking a
    # changegroup that contains an unacceptable commit followed later
    # by a commit that fixes the problem.
    tip = repo['tip']
    for rev in xrange(len(repo) - 1, repo[node].rev() - 1, -1):
        c = repo[rev]
        for f in c.files():
            if f in seen or f not in tip or f not in c:
                continue
            seen.add(f)
            data = c[f].data()
            if not util.binary(data) and newline in data:
                if not halt:
                    ui.warn(_('attempt to commit or push text file(s) '
                              'using %s line endings\n') %
                              newlinestr[newline])
                ui.warn(_('in %s: %s\n') % (short(c.node()), f))
                halt = True
    if halt and hooktype == 'pretxnchangegroup':
        crlf = newlinestr[newline].lower()
        filter = filterstr[newline]
        ui.warn(_('\nTo prevent this mistake in your local repository,\n'
                  'add to Mercurial.ini or .hg/hgrc:\n'
                  '\n'
                  '[hooks]\n'
                  'pretxncommit.%s = python:hgext.win32text.forbid%s\n'
                  '\n'
                  'and also consider adding:\n'
                  '\n'
                  '[extensions]\n'
                  'win32text =\n'
                  '[encode]\n'
                  '** = %sencode:\n'
                  '[decode]\n'
                  '** = %sdecode:\n') % (crlf, crlf, filter, filter))
    return halt

def forbidcrlf(ui, repo, hooktype, node, **kwargs):
    return forbidnewline(ui, repo, hooktype, node, '\r\n', **kwargs)

def forbidcr(ui, repo, hooktype, node, **kwargs):
    return forbidnewline(ui, repo, hooktype, node, '\r', **kwargs)

def reposetup(ui, repo):
    if not repo.local():
        return
    for name, fn in _filters.iteritems():
        repo.adddatafilter(name, fn)

def extsetup(ui):
    # deprecated config: win32text.warn
    if ui.configbool('win32text', 'warn'):
        ui.warn(_("win32text is deprecated: "
                  "https://mercurial-scm.org/wiki/Win32TextExtension\n"))