doc/check-seclevel.py

hgweb: code selection without line numbers in file source view

All the source lines are put in a <pre> tag, which gives correct display and
copy&paste in both Chromium (WebKit) and FireFox: line numbers are not copied,
all the tabs and spaces are kept. This doesn't change the visual appearance
of the view compared to current hgweb version and doesn't use any JS code.
Also, stripes in this view are now generated clientside with CSS.

This implementation is chosen because other variants have important issues:

Strategy             FF              Chrome

current             D,LT,E,T,L        D,L
pre                 S,NW              S,NW
pre/div/nbsp        LT,E,T,TS,NW      TS,NW
pre/div/br          LT,E,T,NW         NW
ol/li/nbsp          LT,E,T,TS,AJ      TS,AJ
ol/li/br            LT,E,T,AJ         AJ
pre/span            LV                LV

Legend

Strategies:
- current: implemented in hgweb before this patch, i.e. divs for each line,
and line numbers links in the div too
- pre: the whole code in one pre tag with newlines, all line numbers
in another one with 'float: left'
- pre/div/{nbsp,br}: same as just 'pre', but separate divs for each line and
&nbsp; or <br> instead of empty lines (otherwise they are not copied at all)
- ol/li/{nbsp,br}: a single ol with li's and divs for each line,
&nbsp; or <br> same as in previous strategy
- pre/span: this patch

Problems:
D = (very minor) display problems, like wrong width of leading tabs
LT = loses leading/trailing whitespace
E = loses embedded whitespace
B = loses blank lines
T = loses tabs
L = selects line numbers
LV = (only) visually selects line numbers
LVE = (only) visually selects line numbers at empty lines
S = no stripes (and no ability to easily highlight
lines-which-are-linked-at in the future)
TS = space copied instead of empty line
AJ = get anchor links only with JS (they work even without)
NW = no linewrap easily possible (in future)

As for browser versions compatibility, the CSS tricks used are supported in
(according to caniuse.com):
a) line numbers generation with 'content:' property and CSS counters:
IE 8+, all other popular browsers (in pre-WebKit Opera numbers are being copied)
b) stripes ('nth-child' selector):
IE 8+, FF 3.5+, Safari 3.2+, Opera 9.5+, all other popular browsers
c) line numbers are not visually selected ('user-select:' property):
IE 10+, Opera 15.0+, all other popular browsers

This patch is based on a demo implementation by
Martin Geisler <[e-mail]>.

#!/usr/bin/env python
#
# checkseclevel - checking section title levels in each online help documents

import sys, os
import optparse

# import from the live mercurial repo
sys.path.insert(0, "..")
# fall back to pure modules if required C extensions are not available
sys.path.append(os.path.join('..', 'mercurial', 'pure'))
from mercurial import demandimport; demandimport.enable()
from mercurial.commands import table
from mercurial.help import helptable
from mercurial import extensions
from mercurial import minirst
from mercurial import util

_verbose = False

def verbose(msg):
    if _verbose:
        print msg

def error(msg):
    sys.stderr.write('%s\n' % msg)

level2mark = ['"', '=', '-', '.', '#']
reservedmarks = ['"']

mark2level = {}
for m, l in zip(level2mark, xrange(len(level2mark))):
    if m not in reservedmarks:
        mark2level[m] = l

initlevel_topic = 0
initlevel_cmd = 1
initlevel_ext = 1
initlevel_ext_cmd = 3

def showavailables(initlevel):
    error('    available marks and order of them in this help: %s' %
          (', '.join(['%r' % (m * 4) for m in level2mark[initlevel + 1:]])))

def checkseclevel(doc, name, initlevel):
    verbose('checking "%s"' % name)
    blocks, pruned = minirst.parse(doc, 0, ['verbose'])
    errorcnt = 0
    curlevel = initlevel
    for block in blocks:
        if block['type'] != 'section':
            continue
        mark = block['underline']
        title = block['lines'][0]
        if (mark not in mark2level) or (mark2level[mark] <= initlevel):
            error('invalid section mark %r for "%s" of %s' %
                  (mark * 4, title, name))
            showavailables(initlevel)
            errorcnt += 1
            continue
        nextlevel = mark2level[mark]
        if curlevel < nextlevel and curlevel + 1 != nextlevel:
            error('gap of section level at "%s" of %s' %
                  (title, name))
            showavailables(initlevel)
            errorcnt += 1
            continue
        verbose('appropriate section level for "%s %s"' %
                (mark * (nextlevel * 2), title))
        curlevel = nextlevel

    return errorcnt

def checkcmdtable(cmdtable, namefmt, initlevel):
    errorcnt = 0
    for k, entry in cmdtable.items():
        name = k.split("|")[0].lstrip("^")
        if not entry[0].__doc__:
            verbose('skip checking %s: no help document' %
                    (namefmt % name))
            continue
        errorcnt += checkseclevel(entry[0].__doc__,
                                  namefmt % name,
                                  initlevel)
    return errorcnt

def checkhghelps():
    errorcnt = 0
    for names, sec, doc in helptable:
        if util.safehasattr(doc, '__call__'):
            doc = doc()
        errorcnt += checkseclevel(doc,
                                  '%s help topic' % names[0],
                                  initlevel_topic)

    errorcnt += checkcmdtable(table, '%s command', initlevel_cmd)

    for name in sorted(extensions.enabled().keys() +
                       extensions.disabled().keys()):
        mod = extensions.load(None, name, None)
        if not mod.__doc__:
            verbose('skip checking %s extension: no help document' % name)
            continue
        errorcnt += checkseclevel(mod.__doc__,
                                  '%s extension' % name,
                                  initlevel_ext)

        cmdtable = getattr(mod, 'cmdtable', None)
        if cmdtable:
            errorcnt += checkcmdtable(cmdtable,
                                      '%s command of ' + name + ' extension',
                                      initlevel_ext_cmd)
    return errorcnt

def checkfile(filename, initlevel):
    if filename == '-':
        filename = 'stdin'
        doc = sys.stdin.read()
    else:
        fp = open(filename)
        try:
            doc = fp.read()
        finally:
            fp.close()

    verbose('checking input from %s with initlevel %d' %
            (filename, initlevel))
    return checkseclevel(doc, 'input from %s' % filename, initlevel)

if __name__ == "__main__":
    optparser = optparse.OptionParser("""%prog [options]

This checks all help documents of Mercurial (topics, commands,
extensions and commands of them), if no file is specified by --file
option.
""")
    optparser.add_option("-v", "--verbose",
                         help="enable additional output",
                         action="store_true")
    optparser.add_option("-f", "--file",
                         help="filename to read in (or '-' for stdin)",
                         action="store", default="")

    optparser.add_option("-t", "--topic",
                         help="parse file as help topic",
                         action="store_const", dest="initlevel", const=0)
    optparser.add_option("-c", "--command",
                         help="parse file as help of core command",
                         action="store_const", dest="initlevel", const=1)
    optparser.add_option("-e", "--extension",
                         help="parse file as help of extension",
                         action="store_const", dest="initlevel", const=1)
    optparser.add_option("-C", "--extension-command",
                         help="parse file as help of extension command",
                         action="store_const", dest="initlevel", const=3)

    optparser.add_option("-l", "--initlevel",
                         help="set initial section level manually",
                         action="store", type="int", default=0)

    (options, args) = optparser.parse_args()

    _verbose = options.verbose

    if options.file:
        if checkfile(options.file, options.initlevel):
            sys.exit(1)
    else:
        if checkhghelps():
            sys.exit(1)