view mercurial/scmposix.py @ 37080:1e30a26a65d0

filemerge: make the 'local' path match the format that 'base' and 'other' use

If we pass a separate '$output' arg to the merge tool, we produce four files:
local, base, other, and output.  In this situation, 'output' will be the
original filename, 'base' and 'other' are temporary files, and previously
'local' would be the backup file (so if 'output' was foo.txt, 'local' would be
foo.txt.orig).

This change makes it so that 'local' follows the same pattern as 'base' and
'other' - it will be a temporary file either in the
`experimental.mergetempdirprefix`-controlled directory with a name like
foo~local.txt, or in the normal system-wide temp dir with a name like
foo~local.RaNd0m.txt.

For the cases where the merge tool does not use an '$output' arg, 'local' is
still the destination filename, and 'base' and 'other' are unchanged.

The hope is that this is much easier for people to reason about; rather than
having a tool like Meld pop up with three panes, one of them with the filename
"foo.txt.orig", one with the filename "foo.txt", and one with
"foo~other.StuFf2.txt", we can (when the merge temp dir stuff is enabled) make
it show up as "foo~local.txt", "foo.txt" and "foo~other.txt", respectively.

This also opens the door to future customization, such as getting the
operation-provided labels and a hash prefix into the filenames (so we see
something like "foo~dest.abc123", "foo.txt", and "foo~src.d4e5f6").

Differential Revision: https://phab.mercurial-scm.org/D2889

from __future__ import absolute_import

import array
import errno
import fcntl
import os
import sys

from . import (
    encoding,
    pycompat,
    util,
)

# BSD 'more' escapes ANSI color sequences by default. This can be disabled by
# $MORE variable, but there's no compatible option with Linux 'more'. Given
# OS X is widely used and most modern Unix systems would have 'less', setting
# 'less' as the default seems reasonable.
fallbackpager = 'less'

def _rcfiles(path):
    rcs = [os.path.join(path, 'hgrc')]
    rcdir = os.path.join(path, 'hgrc.d')
    try:
        rcs.extend([os.path.join(rcdir, f)
                    for f, kind in util.listdir(rcdir)
                    if f.endswith(".rc")])
    except OSError:
        pass
    return rcs

def systemrcpath():
    path = []
    if pycompat.sysplatform == 'plan9':
        root = 'lib/mercurial'
    else:
        root = 'etc/mercurial'
    # old mod_python does not set sys.argv
    if len(getattr(sys, 'argv', [])) > 0:
        p = os.path.dirname(os.path.dirname(pycompat.sysargv[0]))
        if p != '/':
            path.extend(_rcfiles(os.path.join(p, root)))
    path.extend(_rcfiles('/' + root))
    return path

def userrcpath():
    if pycompat.sysplatform == 'plan9':
        return [encoding.environ['home'] + '/lib/hgrc']
    elif pycompat.isdarwin:
        return [os.path.expanduser('~/.hgrc')]
    else:
        confighome = encoding.environ.get('XDG_CONFIG_HOME')
        if confighome is None or not os.path.isabs(confighome):
            confighome = os.path.expanduser('~/.config')

        return [os.path.expanduser('~/.hgrc'),
                os.path.join(confighome, 'hg', 'hgrc')]

def termsize(ui):
    try:
        import termios
        TIOCGWINSZ = termios.TIOCGWINSZ  # unavailable on IRIX (issue3449)
    except (AttributeError, ImportError):
        return 80, 24

    for dev in (ui.ferr, ui.fout, ui.fin):
        try:
            try:
                fd = dev.fileno()
            except AttributeError:
                continue
            if not os.isatty(fd):
                continue
            arri = fcntl.ioctl(fd, TIOCGWINSZ, '\0' * 8)
            height, width = array.array(r'h', arri)[:2]
            if width > 0 and height > 0:
                return width, height
        except ValueError:
            pass
        except IOError as e:
            if e[0] == errno.EINVAL:
                pass
            else:
                raise
    return 80, 24