view hgext/beautifygraph.py @ 38717:aa21a9ad46ea

sparse-revlog: new requirement enabled with format.sparse-revlog

The meaning of the new 'sparse-revlog' requirement is that the revlogs are
allowed to contain wider delta chains with larger holes between the interesting
chunks. These sparse delta chains should be read in several chunks to avoid a
potential explosion of memory usage.

Former version won't know how to read a delta chain in several chunks. They
would keep reading them in a single read, and therefore would be subject to the
potential memory explosion. Hence this new requirement: only versions having
support of sparse-revlog reading should be allowed to read such a revlog.

Implementation of this new algorithm and tools to enable or disable the
requirement will follow in the next changesets.

# -*- 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,
    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 == 'X':
        return '\xE2\x95\xB3' # U+2573 ╳
    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 xrange(len(line) - 2):
        pretty.append(prettyedge(line[idx], line[idx + 1], line[idx + 2]))
    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 encoding.encoding != 'UTF-8':
        ui.warn(_('beautifygraph: unsupported encoding, UTF-8 required\n'))
        return

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

    if ui.plain('graph'):
        return

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