hgext/highlight.py

hook: redirect stdout to stderr for ssh and http servers

"""
This is Mercurial extension for syntax highlighting in the file
revision view of hgweb.

It depends on the pygments syntax highlighting library:
http://pygments.org/

To enable the extension add this to hgrc:

[extensions]
hgext.highlight =

There is a single configuration option:

[web]
pygments_style = <style>

The default is 'colorful'.  If this is changed the corresponding CSS
file should be re-generated by running

# pygmentize -f html -S <newstyle>


-- Adam Hupp <[e-mail]>


"""

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

import mimetypes

from mercurial.hgweb import hgweb_mod
from mercurial.hgweb.hgweb_mod import hgweb
from mercurial import util
from mercurial.hgweb.common import paritygen
from mercurial.node import hex

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

SYNTAX_CSS = ('\n<link rel="stylesheet" href="#staticurl#highlight.css" '
              'type="text/css" />')

class StripedHtmlFormatter(HtmlFormatter):
    def __init__(self, stripecount, *args, **kwargs):
        super(StripedHtmlFormatter, self).__init__(*args, **kwargs)
        self.stripecount = stripecount

    def wrap(self, source, outfile):
        yield 0, "<div class='highlight'>"
        yield 0, "<pre>"
        parity = paritygen(self.stripecount)

        for n, i in source:
            if n == 1:
                i = "<div class='parity%s'>%s</div>" % (parity.next(), i)
            yield n, i

        yield 0, "</pre>"
        yield 0, "</div>"


def pygments_format(filename, text, forcetext, stripecount, style):
    if not forcetext:
        try:
            lexer = guess_lexer_for_filename(filename, text,
                                             encoding=util._encoding)
        except ClassNotFound:
            lexer = TextLexer(encoding=util._encoding)
    else:
        lexer = TextLexer(encoding=util._encoding)

    formatter = StripedHtmlFormatter(stripecount, style=style,
                                     linenos='inline', encoding=util._encoding)

    return highlight(text, lexer, formatter)


def filerevision_pygments(self, tmpl, fctx):
    """Reimplement hgweb.filerevision to use syntax highlighting"""
    f = fctx.path()

    rawtext = fctx.data()
    text = rawtext

    fl = fctx.filelog()
    n = fctx.filenode()

    mt = mimetypes.guess_type(f)[0]

    # we always want hgweb.encoding
    util._encoding = self.encoding

    if util.binary(text):
        mt = mt or 'application/octet-stream'
        text = "(binary:%s)" % mt

        # don't parse (binary:...) as anything
        forcetext = True
    else:
        mt = mt or 'text/plain'

        # encode to hgweb.encoding for lexers and formatter
        text = util.tolocal(text)
        forcetext = False

    def lines(text):
        for line in text.splitlines(True):
            yield {"line": line}

    style = self.config("web", "pygments_style", "colorful")

    text_formatted = lines(pygments_format(f, text, forcetext,
                                           self.stripecount, style))

    # override per-line template
    tmpl.cache['fileline'] = '#line#'

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

    yield tmpl("filerevision",
               file=f,
               path=hgweb_mod._up(f), # fixme: make public
               text=text_formatted,
               raw=rawtext,
               mimetype=mt,
               rev=fctx.rev(),
               node=hex(fctx.node()),
               author=fctx.user(),
               date=fctx.date(),
               desc=fctx.description(),
               parent=self.siblings(fctx.parents()),
               child=self.siblings(fctx.children()),
               rename=self.renamelink(fl, n),
               permissions=fctx.manifest().flags(f))


# monkeypatch in the new version
# should be safer than overriding the method in a derived class
# and then patching the class
hgweb.filerevision = filerevision_pygments