[stgit] / stgit / commands / repair.py

# -*- coding: utf-8 -*-

__copyright__ = """
Copyright (C) 2006, Karl Hasselström <kha@treskal.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as
published by the Free Software Foundation.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""

import sys, os
from optparse import OptionParser, make_option

from stgit.commands.common import *
from stgit.utils import *
from stgit.out import *
from stgit.run import *
from stgit import stack, git

help = 'StGit-ify any git commits made on top of your StGit stack'
usage = """%prog [options]

"repair" will repair three kinds of inconsistencies in your StGit
stack, all of them caused by using plain git commands on the branch:

  1. If you have made regular git commits on top of your stack of
     StGit patches, "repair" converts them to StGit patches,
     preserving their contents.

  2. Merge commits cannot become patches; if you have committed a
     merge on top of your stack, "repair" will simply mark all
     patches below the merge unapplied, since they are no longer
     reachable. If this is not what you want, use "git reset" to get
     rid of the merge and run "repair" again.

  3. The applied patches are supposed to be precisely those that are
     reachable from the branch head. If you have used e.g. "git reset"
     to move the head, some applied patches may no longer be
     reachable, and some unapplied patches may have become reachable.
     "repair" will correct the appliedness of such patches.

Note that these are "inconsistencies", not "errors"; furthermore,
"repair" will repair them reliably. As long as you are satisfied
with the way "repair" handles them, you have no reason to avoid
causing them in the first place if that is convenient for you."""

directory = DirectoryGotoToplevel()
options = []

class Commit(object):
    def __init__(self, id):
        self.id = id
        self.parents = set()
        self.children = set()
        self.patch = None
        self.__commit = None
    def __get_commit(self):
        if not self.__commit:
            self.__commit = git.get_commit(self.id)
        return self.__commit
    commit = property(__get_commit)
    def __str__(self):
        if self.patch:
            return '%s (%s)' % (self.id, self.patch)
        else:
            return self.id
    def __repr__(self):
        return '<%s>' % str(self)

def read_commit_dag(branch):
    out.start('Reading commit DAG')
    commits = {}
    patches = set()
    for line in Run('git', 'rev-list', '--parents', '--all').output_lines():
        cs = line.split()
        for id in cs:
            if not id in commits:
                commits[id] = Commit(id)
        for id in cs[1:]:
            commits[cs[0]].parents.add(commits[id])
            commits[id].children.add(commits[cs[0]])
    for line in Run('git', 'show-ref').output_lines():
        id, ref = line.split()
        m = re.match(r'^refs/patches/%s/(.+)$' % branch, ref)
        if m and not m.group(1).endswith('.log'):
            c = commits[id]
            c.patch = m.group(1)
            patches.add(c)
    out.done()
    return commits, patches

def func(parser, options, args):
    """Repair inconsistencies in StGit metadata."""

    orig_applied = crt_series.get_applied()
    orig_unapplied = crt_series.get_unapplied()

    if crt_series.get_protected():
        raise CmdException(
            'This branch is protected. Modification is not permitted.')

    # Find commits that aren't patches, and applied patches.
    head = git.get_commit(git.get_head()).get_id_hash()
    commits, patches = read_commit_dag(crt_series.get_name())
    c = commits[head]
    patchify = []       # commits to definitely patchify
    maybe_patchify = [] # commits to patchify if we find a patch below them
    applied = []
    while len(c.parents) == 1:
        parent, = c.parents
        if c.patch:
            applied.append(c)
            patchify.extend(maybe_patchify)
            maybe_patchify = []
        else:
            maybe_patchify.append(c)
        c = parent
    applied.reverse()
    patchify.reverse()

    # Find patches hidden behind a merge.
    merge = c
    todo = set([c])
    seen = set()
    hidden = set()
    while todo:
        c = todo.pop()
        seen.add(c)
        todo |= c.parents - seen
        if c.patch:
            hidden.add(c)
    if hidden:
        out.warn(('%d patch%s are hidden below the merge commit'
                  % (len(hidden), ['es', ''][len(hidden) == 1])),
                 '%s,' % merge.id, 'and will be considered unapplied.')

    # Make patches of any linear sequence of commits on top of a patch.
    names = set(p.patch for p in patches)
    def name_taken(name):
        return name in names
    if applied and patchify:
        out.start('Creating %d new patch%s'
                  % (len(patchify), ['es', ''][len(patchify) == 1]))
        for p in patchify:
            name = make_patch_name(p.commit.get_log(), name_taken)
            out.info('Creating patch %s from commit %s' % (name, p.id))
            aname, amail, adate = name_email_date(p.commit.get_author())
            cname, cmail, cdate = name_email_date(p.commit.get_committer())
            parent, = p.parents
            crt_series.new_patch(
                name, can_edit = False, commit = False,
                top = p.id, bottom = parent.id, message = p.commit.get_log(),
                author_name = aname, author_email = amail, author_date = adate,
                committer_name = cname, committer_email = cmail)
            p.patch = name
            applied.append(p)
            names.add(name)
        out.done()

    # Write the applied/unapplied files.
    out.start('Checking patch appliedness')
    unapplied = patches - set(applied)
    applied_name_set = set(p.patch for p in applied)
    unapplied_name_set = set(p.patch for p in unapplied)
    patches_name_set = set(p.patch for p in patches)
    orig_patches = orig_applied + orig_unapplied
    orig_applied_name_set = set(orig_applied)
    orig_unapplied_name_set = set(orig_unapplied)
    orig_patches_name_set = set(orig_patches)
    for name in orig_patches_name_set - patches_name_set:
        out.info('%s is gone' % name)
    for name in applied_name_set - orig_applied_name_set:
        out.info('%s is now applied' % name)
    for name in unapplied_name_set - orig_unapplied_name_set:
        out.info('%s is now unapplied' % name)
    orig_order = dict(zip(orig_patches, xrange(len(orig_patches))))
    def patchname_cmp(p1, p2):
        i1 = orig_order.get(p1, len(orig_order))
        i2 = orig_order.get(p2, len(orig_order))
        return cmp((i1, p1), (i2, p2))
    crt_series.set_applied(p.patch for p in applied)
    crt_series.set_unapplied(sorted(unapplied_name_set, cmp = patchname_cmp))
    out.done()