doc/check-seclevel.py

rebase: exclude descendants of obsoletes w/o a successor in dest (issue5300)

.. feature::

   Let 'hg rebase' avoid content-divergence by skipping obsolete
   changesets (and their descendants) when they are present in the rebase
   set along with one of their successors but none of their successors is
   in destination.

In the following example, when trying to rebase 3:: onto 2, the rebase
will abort with "this rebase will cause divergence from: 4":

    o  7 f
    |
    | o  6 e
    | |
    | o  5 d'
    | |
    x |  4 d (rewritten as 5)
    |/
    o  3 c
    |
    | o  2 x
    | |
    o |  1 b
    |/
    o  0 a

By excluding obsolete changesets without a successor in destination (4
in the example above) and their descendants, we make rebase work in this
case, thus giving:

    o  11 e
    |
    o  10 d'
    |
    o  9 c
    |
    o  8 b
    |
    | o  7 f
    | |
    | | x  6 e (rewritten using rebase as 11)
    | | |
    | | x  5 d' (rewritten using rebase as 10)
    | | |
    | x |  4 d
    | |/
    | x  3 c (rewritten using rebase as 9)
    | |
    o |  2 x
    | |
    | x  1 b (rewritten using rebase as 8)
    |/
    o  0 a

where branch 4:: is left behind while branch 5:: is rebased as expected.

The rationale is that users may not be interested in rebasing orphan
changesets when specifying a rebase set that include them but would
still want "stable" ones to be rebased. Currently, the user is suggested
to allow divergence (but probably does not want it) or they must specify
a rebase set excluding problematic changesets (which might be a bit
cumbersome). The approach proposed here corresponds to "Option 2" in
https://www.mercurial-scm.org/wiki/CEDRebase.


We extend _computeobsoletenotrebased() so that it also return a set of
obsolete changesets in rebase set without a successor in destination but
with at least one successor in rebase set. This
'obsoletewithoutsuccessorindestination' is then stored as an attribute
of rebaseruntime and used in _performrebasesubset() to:

* filter out descendants of these changesets from the revisions to
  rebase;
* issue a message about these revisions being skipped.

This only occurs if 'evolution.allowdivergence' option is off and
'rebaseskipobsolete' is on.

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

from __future__ import absolute_import

import optparse
import os
import sys

# import from the live mercurial repo
os.environ['HGMODULEPOLICY'] = 'py'
sys.path.insert(0, "..")
from mercurial import demandimport; demandimport.enable()
from mercurial import (
    commands,
    extensions,
    help,
    minirst,
    ui as uimod,
)

table = commands.table
helptable = help.helptable

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

mark2level = {}
for m, l in zip(level2mark, range(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(ui, initlevel):
    avail = ('    available marks and order of them in this help: %s\n') % (
        ', '.join(['%r' % (m * 4) for m in level2mark[initlevel + 1:]]))
    ui.warn(avail.encode('utf-8'))

def checkseclevel(ui, doc, name, initlevel):
    ui.note(('checking "%s"\n') % name)
    if not isinstance(doc, bytes):
        doc = doc.encode('utf-8')
    blocks, pruned = minirst.parse(doc, 0, ['verbose'])
    errorcnt = 0
    curlevel = initlevel
    for block in blocks:
        if block[b'type'] != b'section':
            continue
        mark = block[b'underline']
        title = block[b'lines'][0]
        if (mark not in mark2level) or (mark2level[mark] <= initlevel):
            ui.warn((('invalid section mark %r for "%s" of %s\n') %
                     (mark * 4, title, name)).encode('utf-8'))
            showavailables(ui, initlevel)
            errorcnt += 1
            continue
        nextlevel = mark2level[mark]
        if curlevel < nextlevel and curlevel + 1 != nextlevel:
            ui.warn(('gap of section level at "%s" of %s\n') %
                    (title, name))
            showavailables(ui, initlevel)
            errorcnt += 1
            continue
        ui.note(('appropriate section level for "%s %s"\n') %
                (mark * (nextlevel * 2), title))
        curlevel = nextlevel

    return errorcnt

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

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

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

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

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

def checkfile(ui, filename, initlevel):
    if filename == '-':
        filename = 'stdin'
        doc = sys.stdin.read()
    else:
        with open(filename) as fp:
            doc = fp.read()

    ui.note(('checking input from %s with initlevel %d\n') %
            (filename, initlevel))
    return checkseclevel(ui, doc, 'input from %s' % filename, initlevel)

def 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("-d", "--debug",
                         help="debug mode",
                         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()

    ui = uimod.ui.load()
    ui.setconfig('ui', 'verbose', options.verbose, '--verbose')
    ui.setconfig('ui', 'debug', options.debug, '--debug')

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

if __name__ == "__main__":
    main()