hgext/beautifygraph.py

revlog: document that mmap resources are released implicitly by GC

It's okay-ish, but currently the open fd and the mapping itself are leaked
until the indexdata is deallocated. If revlog had close(), the underlying
resources should be closed there as well, but AFAIK there's no such hook
point.

# -*- coding: UTF-8 -*-
# beautifygraph.py - improve graph output by using Unicode characters
#
# Copyright 2018 John Stiles <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''beautify log -G output by using Unicode characters (EXPERIMENTAL)

   A terminal with UTF-8 support and monospace narrow text are required.
'''

from __future__ import absolute_import

from mercurial.i18n import _
from mercurial import (
    encoding,
    extensions,
    graphmod,
    pycompat,
    templatekw,
)

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'

def prettyedge(before, edge, after):
    if edge == '~':
        return '\xE2\x95\xA7' # U+2567 ╧
    if edge == '/':
        return '\xE2\x95\xB1' # U+2571 ╱
    if edge == '-':
        return '\xE2\x94\x80' # U+2500 ─
    if edge == '|':
        return '\xE2\x94\x82' # U+2502 │
    if edge == ':':
        return '\xE2\x94\x86' # U+2506 ┆
    if edge == '\\':
        return '\xE2\x95\xB2' # U+2572 ╲
    if edge == '+':
        if before == ' ' and not after  == ' ':
            return '\xE2\x94\x9C' # U+251C ├
        if after  == ' ' and not before == ' ':
            return '\xE2\x94\xA4' # U+2524 ┤
        return '\xE2\x94\xBC' # U+253C ┼
    return edge

def convertedges(line):
    line = ' %s ' % line
    pretty = []
    for idx in pycompat.xrange(len(line) - 2):
        pretty.append(prettyedge(line[idx:idx + 1],
                                 line[idx + 1:idx + 2],
                                 line[idx + 2:idx + 3]))
    return ''.join(pretty)

def getprettygraphnode(orig, *args, **kwargs):
    node = orig(*args, **kwargs)
    if node == 'o':
        return '\xE2\x97\x8B' # U+25CB ○
    if node == '@':
        return '\xE2\x97\x8D' # U+25CD ◍
    if node == '*':
        return '\xE2\x88\x97' # U+2217 ∗
    if node == 'x':
        return '\xE2\x97\x8C' # U+25CC ◌
    if node == '_':
        return '\xE2\x95\xA4' # U+2564 ╤
    return node

def outputprettygraph(orig, ui, graph, *args, **kwargs):
    (edges, text) = zip(*graph)
    graph = zip([convertedges(e) for e in edges], text)
    return orig(ui, graph, *args, **kwargs)

def extsetup(ui):
    if ui.plain('graph'):
        return

    if encoding.encoding != 'UTF-8':
        ui.warn(_('beautifygraph: unsupported encoding, UTF-8 required\n'))
        return

    if r'A' in encoding._wide:
        ui.warn(_('beautifygraph: unsupported terminal settings, '
                  'monospace narrow text required\n'))
        return

    extensions.wrapfunction(graphmod, 'outputgraph', outputprettygraph)
    extensions.wrapfunction(templatekw, 'getgraphnode', getprettygraphnode)