view mercurial/scmposix.py @ 30661:ced0d686ecb3

convert: add config option to control storing original revision

common.commit.__init__ sets saverev=True by default. The side effect
of this is that the hg sink will always set the "convert_revision"
extras key to the commit being converted.

This patch adds a config option to disable this behavior.

While most consumers will want "convert_revision" to be a) written
b) with the exact Git commit that was converted, some have use cases
that prefer otherwise. In my case, I am performing significant
rewrites of a Git repository *before* it is fed into `hg convert`.
I have to do this because `hg convert` does not easily support the kind
of transform I desire, even with extensions. (For the curious, I am
"linearizing" the history of a GitHub repo by removing merge commits
which add little value to the final history. It isn't easy to do this
during `hg convert` because of Mercurial's file copy/rename metadata
requirements.)

In my scenario, my pre-convert transform stores a "convert_revision"
key in the Git commit object containing the original Git commit ID.
I want this original Git commit ID carried forward to Mercurial. By
disabling the setting of this extra during `hg convert` and copying
the value from the Git commit object, I can have the final
"convert_revision" extra key contain the original Git commit ID. An
added test verifies this exact scenario.

This feature could likely be implemented for other VCS sources. But
until someone needs the feature, I'm inclined to hold off implementing.

from __future__ import absolute_import

import array
import errno
import fcntl
import os
import sys

from . import (
    encoding,
    osutil,
    pycompat,
)

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 osutil.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']
    else:
        return [os.path.expanduser('~/.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('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