contrib/debugshell.py

rebase: don't rebase obsolete commit whose successor is already rebased

This patch avoids unnecessary conflicts to resolve during rebase for the users
of changeset evolution.

This patch modifies rebase to skip obsolete commits if they are being rebased on
their successors.
It introduces a new rebase state 'revprecursor' for these revisions that are
being skipped and a new message to inform the user of what is happening.
This feature is gated behind the config flag experimental.rebaseskipobsolete

When an obsolete commit is skipped, the output is:
not rebasing 14:9ad579b4a5de "I", already in destination as 17:fc37a630c901 "K"

# debugshell extension
"""a python shell with repo, changelog & manifest objects"""

import sys
import mercurial
import code
from mercurial import cmdutil

cmdtable = {}
command = cmdutil.command(cmdtable)

def pdb(ui, repo, msg, **opts):
    objects = {
        'mercurial': mercurial,
        'repo': repo,
        'cl': repo.changelog,
        'mf': repo.manifest,
    }

    code.interact(msg, local=objects)

def ipdb(ui, repo, msg, **opts):
    import IPython

    cl = repo.changelog
    mf = repo.manifest
    cl, mf # use variables to appease pyflakes

    IPython.embed()

@command('debugshell|dbsh', [])
def debugshell(ui, repo, **opts):
    bannermsg = "loaded repo : %s\n" \
                "using source: %s" % (repo.root,
                                      mercurial.__path__[0])

    pdbmap = {
        'pdb'  : 'code',
        'ipdb' : 'IPython'
    }

    debugger = ui.config("ui", "debugger")
    if not debugger:
        debugger = 'pdb'

    # if IPython doesn't exist, fallback to code.interact
    try:
        __import__(pdbmap[debugger])
    except ImportError:
        ui.warn("%s debugger specified but %s module was not found\n"
                % (debugger, pdbmap[debugger]))
        debugger = 'pdb'

    getattr(sys.modules[__name__], debugger)(ui, repo, bannermsg, **opts)