view hgext/highlight/highlight.py @ 25602:85fb416f2fa7

hgweb: provide symrev (symbolic revision) property to the templates

One of the features of hgweb is that current position in repo history is
remembered between separate requests. That is, links from /rev/<node_hash> lead
to /file/<node_hash> or /log/<node_hash>, so it's easy to dig deep into the
history. However, such links could only use node hashes and local revision
numbers, so while staying at one exact revision is easy, staying on top of the
changes is not, because hashes presumably can't change (local revision numbers
can, but probably not in a way you'd find useful for navigating).

So while you could use 'tip' or 'default' in a url, links on that page would be
permanent. This is not always desired (think /rev/tip or /graph/stable or
/log/@) and is sometimes just confusing (i.e. /log/<not the tip hash>, when
recent history is not displayed). And if user changed url deliberately to say
default instead of <some node hash>, the page ignores that fact and uses node
hash in its links, which means that navigation is, in a way, broken.

This new property, symrev, is used for storing current revision the way it was
specified, so then templates can use it in links and thus "not dereference" the
symbolic revision. It is an additional way to produce links, so not every link
needs to drop {node|short} in favor of {symrev}, many will still use node hash
(log and filelog entries, annotate lines, etc).

Some pages (e.g. summary, tags) always use the tip changeset for their context,
in such cases symrev is set to 'tip'. This is needed in case the pages want to
provide archive links.

highlight extension needs to be updated, since _filerevision now takes an
additional positional argument (signature "web, req, tmpl" is used by most of
webcommands.py functions).

More references to symbolic revisions and related gripes: issue2296, issue2826,
issue3594, issue3634.

# highlight.py - highlight extension implementation file
#
#  Copyright 2007-2009 Adam Hupp <[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.
#
# The original module was split in an interface and an implementation
# file to defer pygments loading and speedup extension setup.

from mercurial import demandimport
demandimport.ignore.extend(['pkgutil', 'pkg_resources', '__main__'])
from mercurial import util, encoding

from pygments import highlight
from pygments.util import ClassNotFound
from pygments.lexers import guess_lexer, guess_lexer_for_filename, TextLexer
from pygments.formatters import HtmlFormatter

SYNTAX_CSS = ('\n<link rel="stylesheet" href="{url}highlightcss" '
              'type="text/css" />')

def pygmentize(field, fctx, style, tmpl):

    # append a <link ...> to the syntax highlighting css
    old_header = tmpl.load('header')
    if SYNTAX_CSS not in old_header:
        new_header =  old_header + SYNTAX_CSS
        tmpl.cache['header'] = new_header

    text = fctx.data()
    if util.binary(text):
        return

    # str.splitlines() != unicode.splitlines() because "reasons"
    for c in "\x0c\x1c\x1d\x1e":
        if c in text:
            text = text.replace(c, '')

    # Pygments is best used with Unicode strings:
    # <http://pygments.org/docs/unicode/>
    text = text.decode(encoding.encoding, 'replace')

    # To get multi-line strings right, we can't format line-by-line
    try:
        lexer = guess_lexer_for_filename(fctx.path(), text[:1024],
                                         stripnl=False)
    except (ClassNotFound, ValueError):
        try:
            lexer = guess_lexer(text[:1024], stripnl=False)
        except (ClassNotFound, ValueError):
            lexer = TextLexer(stripnl=False)

    formatter = HtmlFormatter(style=style)

    colorized = highlight(text, lexer, formatter)
    # strip wrapping div
    colorized = colorized[:colorized.find('\n</pre>')]
    colorized = colorized[colorized.find('<pre>') + 5:]
    coloriter = (s.encode(encoding.encoding, 'replace')
                 for s in colorized.splitlines())

    tmpl.filters['colorize'] = lambda x: coloriter.next()

    oldl = tmpl.cache[field]
    newl = oldl.replace('line|escape', 'line|colorize')
    tmpl.cache[field] = newl