view doc/check-seclevel.py @ 48507:58a3be48ddd2

simplemerge: stop merging file flags

As 384df4db6520 (merge: merge file flags together with file content,
2013-01-09) explains, we shouldn't do a 3-way merge of the
symlink. However, since 84614212ae39 (flags: actually merge flags in
simplemerge, 2020-05-16), we do that in
`simplemerge.simplemerge()`. What's more, the merging of the
executable flag there isn't actually necessary; it was made a no-op by
the very next commit, i.e. 4234c9af515d (flags: read flag from
dirstate/disk for workingcopyctx (issue5743), 2020-05-16).

I found the overall flag-merging code (not the bit in
`simplemerge.py`) very hard to follow, but I think I now finally
understand how it works. `mergestate.resolve()` calculates the merged
file flags and sets them on the local side of the merge (confusingly
by calling `_restore_backup()`). Then it calls
`filemerge.filemerge()`, which in turn calls
`simplemerge.simplemerge()` (if premerge is enabled). That means that
the flags on the local side `fcs.flags()` are already correct when the
flag-merging code in `simplemerge.simplemerge()` runs. Interestingly,
that code still works when the local side already has the merged
value, it just doesn't change the value. Here's a truth table to
explain why:

```
BLOMCAR
0000000
0011111
0101011
0111111
1000000
1010000
1100000
1111101
```

B: Base
L: Local
O: Other
M: Merged flags from `mergestate.resolve()`, i.e. what's called "local"
   when we get to `simplemerge.simplemerge()`
C: `commonflags` in `simplemerge.simplemerge()`, i.e. `M & O`
A: `addedflags` in `simplemerge.simplemerge()`, i.e. `(M ^ O) - B`
R: Re-merged flags `simplemerge.simplemerge()`, i.e. `C | A`

As you can see, the re-merged flags are always unchanged compared to
the initial merged flags (R equals M).

Therefore, this patch effectively backs out 84614212ae39. (I might
later refactor this code to have the flags explicitly passed in.)

`simplemerge.simplemerge()` is also called from
`contrib/simplemerge.py`, but that code never passes any flags.

Differential Revision: https://phab.mercurial-scm.org/D11879

#!/usr/bin/env python3
#
# 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.notenoi18n('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.warnnoi18n(
                'gap of section level at "%s" of %s\n' % (title, name)
            )
            showavailables(ui, initlevel)
            errorcnt += 1
            continue
        ui.notenoi18n(
            '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.notenoi18n(
                '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 h in helptable:
        names, sec, doc = h[0:3]
        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.notenoi18n(
                '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.notenoi18n(
        '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(b'ui', b'verbose', options.verbose, b'--verbose')
    ui.setconfig(b'ui', b'debug', options.debug, b'--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()