doc/check-seclevel.py

import-checker: establish modern import convention

We introduce a new convention for declaring imports and enforce it via
the import checker script.

The new convention is only active when absolute imports are used, which is
currently nowhere. Keying off "from __future__ import absolute_import" to
engage the new import convention seems like the easiest solution. It is
also beneficial for Mercurial to use this mode because it means less work
and ambiguity for the importer and potentially better performance due to
fewer stat() system calls because the importer won't look for modules in
relative paths unless explicitly asked.

Once all files are converted to use absolute import, we can refactor
this code to again only have a single import convention and we can
require use of absolute import in the style checker.

The rules for the new convention are documented in the docstring of the
added function. Tests have been added to test-module-imports.t. Some
tests are sensitive to newlines and source column position, which makes
docstring testing difficult and/or impossible.

#!/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

_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 callable(doc):
            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)