hgext/convert/git.py

convert: add support for specifying multiple revs

Previously convert could only take one '--rev'. This change allows the user to
specify multiple --rev entries. For instance, this could allow converting
multiple branches (but not all branches) at once from git.

In this first patch, we disable support for this for all sources.  Future
patches will enable it for select sources (like git).

# git.py - git support for the convert extension
#
#  Copyright 2005-2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import os
import subprocess
from mercurial import util, config, error
from mercurial.node import hex, nullid
from mercurial.i18n import _

from common import NoRepo, commit, converter_source, checktool

class submodule(object):
    def __init__(self, path, node, url):
        self.path = path
        self.node = node
        self.url = url

    def hgsub(self):
        return "%s = [git]%s" % (self.path, self.url)

    def hgsubstate(self):
        return "%s %s" % (self.node, self.path)

class convert_git(converter_source):
    # Windows does not support GIT_DIR= construct while other systems
    # cannot remove environment variable. Just assume none have
    # both issues.
    if util.safehasattr(os, 'unsetenv'):
        def gitopen(self, s, err=None):
            prevgitdir = os.environ.get('GIT_DIR')
            os.environ['GIT_DIR'] = self.path
            try:
                if err == subprocess.PIPE:
                    (stdin, stdout, stderr) = util.popen3(s)
                    return stdout
                elif err == subprocess.STDOUT:
                    return self.popen_with_stderr(s)
                else:
                    return util.popen(s, 'rb')
            finally:
                if prevgitdir is None:
                    del os.environ['GIT_DIR']
                else:
                    os.environ['GIT_DIR'] = prevgitdir

        def gitpipe(self, s):
            prevgitdir = os.environ.get('GIT_DIR')
            os.environ['GIT_DIR'] = self.path
            try:
                return util.popen3(s)
            finally:
                if prevgitdir is None:
                    del os.environ['GIT_DIR']
                else:
                    os.environ['GIT_DIR'] = prevgitdir

    else:
        def gitopen(self, s, err=None):
            if err == subprocess.PIPE:
                (sin, so, se) = util.popen3('GIT_DIR=%s %s' % (self.path, s))
                return so
            elif err == subprocess.STDOUT:
                    return self.popen_with_stderr(s)
            else:
                return util.popen('GIT_DIR=%s %s' % (self.path, s), 'rb')

        def gitpipe(self, s):
            return util.popen3('GIT_DIR=%s %s' % (self.path, s))

    def popen_with_stderr(self, s):
        p = subprocess.Popen(s, shell=True, bufsize=-1,
                             close_fds=util.closefds,
                             stdin=subprocess.PIPE,
                             stdout=subprocess.PIPE,
                             stderr=subprocess.STDOUT,
                             universal_newlines=False,
                             env=None)
        return p.stdout

    def gitread(self, s):
        fh = self.gitopen(s)
        data = fh.read()
        return data, fh.close()

    def __init__(self, ui, path, revs=None):
        super(convert_git, self).__init__(ui, path, revs=revs)

        if revs and len(revs) > 1:
            raise util.Abort(_("git source does not support specifying "
                               "multiple revs"))

        if os.path.isdir(path + "/.git"):
            path += "/.git"
        if not os.path.exists(path + "/objects"):
            raise NoRepo(_("%s does not look like a Git repository") % path)

        # The default value (50) is based on the default for 'git diff'.
        similarity = ui.configint('convert', 'git.similarity', default=50)
        if similarity < 0 or similarity > 100:
            raise util.Abort(_('similarity must be between 0 and 100'))
        if similarity > 0:
            self.simopt = '-C%d%%' % similarity
            findcopiesharder = ui.configbool('convert', 'git.findcopiesharder',
                                             False)
            if findcopiesharder:
                self.simopt += ' --find-copies-harder'
        else:
            self.simopt = ''

        checktool('git', 'git')

        self.path = path
        self.submodules = []

        self.catfilepipe = self.gitpipe('git cat-file --batch')

    def after(self):
        for f in self.catfilepipe:
            f.close()

    def getheads(self):
        if not self.revs:
            heads, ret = self.gitread('git rev-parse --branches --remotes')
            heads = heads.splitlines()
        else:
            heads, ret = self.gitread("git rev-parse --verify %s" %
                                      self.revs[0])
            heads = [heads[:-1]]
        if ret:
            raise util.Abort(_('cannot retrieve git heads'))
        return heads

    def catfile(self, rev, type):
        if rev == hex(nullid):
            raise IOError
        self.catfilepipe[0].write(rev+'\n')
        self.catfilepipe[0].flush()
        info = self.catfilepipe[1].readline().split()
        if info[1] != type:
            raise util.Abort(_('cannot read %r object at %s') % (type, rev))
        size = int(info[2])
        data = self.catfilepipe[1].read(size)
        if len(data) < size:
            raise util.Abort(_('cannot read %r object at %s: unexpected size')
                             % (type, rev))
        # read the trailing newline
        self.catfilepipe[1].read(1)
        return data

    def getfile(self, name, rev):
        if rev == hex(nullid):
            return None, None
        if name == '.hgsub':
            data = '\n'.join([m.hgsub() for m in self.submoditer()])
            mode = ''
        elif name == '.hgsubstate':
            data = '\n'.join([m.hgsubstate() for m in self.submoditer()])
            mode = ''
        else:
            data = self.catfile(rev, "blob")
            mode = self.modecache[(name, rev)]
        return data, mode

    def submoditer(self):
        null = hex(nullid)
        for m in sorted(self.submodules, key=lambda p: p.path):
            if m.node != null:
                yield m

    def parsegitmodules(self, content):
        """Parse the formatted .gitmodules file, example file format:
        [submodule "sub"]\n
        \tpath = sub\n
        \turl = git://giturl\n
        """
        self.submodules = []
        c = config.config()
        # Each item in .gitmodules starts with whitespace that cant be parsed
        c.parse('.gitmodules', '\n'.join(line.strip() for line in
                               content.split('\n')))
        for sec in c.sections():
            s = c[sec]
            if 'url' in s and 'path' in s:
                self.submodules.append(submodule(s['path'], '', s['url']))

    def retrievegitmodules(self, version):
        modules, ret = self.gitread("git show %s:%s" % (version, '.gitmodules'))
        if ret:
            # This can happen if a file is in the repo that has permissions
            # 160000, but there is no .gitmodules file.
            self.ui.warn(_("warning: cannot read submodules config file in "
                           "%s\n") % version)
            return

        try:
            self.parsegitmodules(modules)
        except error.ParseError:
            self.ui.warn(_("warning: unable to parse .gitmodules in %s\n")
                         % version)
            return

        for m in self.submodules:
            node, ret = self.gitread("git rev-parse %s:%s" % (version, m.path))
            if ret:
                continue
            m.node = node.strip()

    def getchanges(self, version, full):
        if full:
            raise util.Abort(_("convert from git do not support --full"))
        self.modecache = {}
        fh = self.gitopen("git diff-tree -z --root -m -r %s %s" % (
            self.simopt, version))
        changes = []
        copies = {}
        seen = set()
        entry = None
        subexists = [False]
        subdeleted = [False]
        difftree = fh.read().split('\x00')
        lcount = len(difftree)
        i = 0

        def add(entry, f, isdest):
            seen.add(f)
            h = entry[3]
            p = (entry[1] == "100755")
            s = (entry[1] == "120000")
            renamesource = (not isdest and entry[4][0] == 'R')

            if f == '.gitmodules':
                subexists[0] = True
                if entry[4] == 'D' or renamesource:
                    subdeleted[0] = True
                    changes.append(('.hgsub', hex(nullid)))
                else:
                    changes.append(('.hgsub', ''))
            elif entry[1] == '160000' or entry[0] == ':160000':
                subexists[0] = True
            else:
                if renamesource:
                    h = hex(nullid)
                self.modecache[(f, h)] = (p and "x") or (s and "l") or ""
                changes.append((f, h))

        while i < lcount:
            l = difftree[i]
            i += 1
            if not entry:
                if not l.startswith(':'):
                    continue
                entry = l.split()
                continue
            f = l
            if f not in seen:
                add(entry, f, False)
            # A file can be copied multiple times, or modified and copied
            # simultaneously. So f can be repeated even if fdest isn't.
            if entry[4][0] in 'RC':
                # rename or copy: next line is the destination
                fdest = difftree[i]
                i += 1
                if fdest not in seen:
                    add(entry, fdest, True)
                    # .gitmodules isn't imported at all, so it being copied to
                    # and fro doesn't really make sense
                    if f != '.gitmodules' and fdest != '.gitmodules':
                        copies[fdest] = f
            entry = None
        if fh.close():
            raise util.Abort(_('cannot read changes in %s') % version)

        if subexists[0]:
            if subdeleted[0]:
                changes.append(('.hgsubstate', hex(nullid)))
            else:
                self.retrievegitmodules(version)
                changes.append(('.hgsubstate', ''))
        return (changes, copies, set())

    def getcommit(self, version):
        c = self.catfile(version, "commit") # read the commit hash
        end = c.find("\n\n")
        message = c[end + 2:]
        message = self.recode(message)
        l = c[:end].splitlines()
        parents = []
        author = committer = None
        for e in l[1:]:
            n, v = e.split(" ", 1)
            if n == "author":
                p = v.split()
                tm, tz = p[-2:]
                author = " ".join(p[:-2])
                if author[0] == "<": author = author[1:-1]
                author = self.recode(author)
            if n == "committer":
                p = v.split()
                tm, tz = p[-2:]
                committer = " ".join(p[:-2])
                if committer[0] == "<": committer = committer[1:-1]
                committer = self.recode(committer)
            if n == "parent":
                parents.append(v)

        if committer and committer != author:
            message += "\ncommitter: %s\n" % committer
        tzs, tzh, tzm = tz[-5:-4] + "1", tz[-4:-2], tz[-2:]
        tz = -int(tzs) * (int(tzh) * 3600 + int(tzm))
        date = tm + " " + str(tz)

        c = commit(parents=parents, date=date, author=author, desc=message,
                   rev=version)
        return c

    def numcommits(self):
        return len([None for _ in self.gitopen('git rev-list --all')])

    def gettags(self):
        tags = {}
        alltags = {}
        fh = self.gitopen('git ls-remote --tags "%s"' % self.path,
                          err=subprocess.STDOUT)
        prefix = 'refs/tags/'

        # Build complete list of tags, both annotated and bare ones
        for line in fh:
            line = line.strip()
            if line.startswith("error:") or line.startswith("fatal:"):
                raise util.Abort(_('cannot read tags from %s') % self.path)
            node, tag = line.split(None, 1)
            if not tag.startswith(prefix):
                continue
            alltags[tag[len(prefix):]] = node
        if fh.close():
            raise util.Abort(_('cannot read tags from %s') % self.path)

        # Filter out tag objects for annotated tag refs
        for tag in alltags:
            if tag.endswith('^{}'):
                tags[tag[:-3]] = alltags[tag]
            else:
                if tag + '^{}' in alltags:
                    continue
                else:
                    tags[tag] = alltags[tag]

        return tags

    def getchangedfiles(self, version, i):
        changes = []
        if i is None:
            fh = self.gitopen("git diff-tree --root -m -r %s" % version)
            for l in fh:
                if "\t" not in l:
                    continue
                m, f = l[:-1].split("\t")
                changes.append(f)
        else:
            fh = self.gitopen('git diff-tree --name-only --root -r %s '
                              '"%s^%s" --' % (version, version, i + 1))
            changes = [f.rstrip('\n') for f in fh]
        if fh.close():
            raise util.Abort(_('cannot read changes in %s') % version)

        return changes

    def getbookmarks(self):
        bookmarks = {}

        # Interesting references in git are prefixed
        prefix = 'refs/heads/'
        prefixlen = len(prefix)

        # factor two commands
        gitcmd = { 'remote/': 'git ls-remote --heads origin',
                          '': 'git show-ref'}

        # Origin heads
        for reftype in gitcmd:
            try:
                fh = self.gitopen(gitcmd[reftype], err=subprocess.PIPE)
                for line in fh:
                    line = line.strip()
                    rev, name = line.split(None, 1)
                    if not name.startswith(prefix):
                        continue
                    name = '%s%s' % (reftype, name[prefixlen:])
                    bookmarks[name] = rev
            except Exception:
                pass

        return bookmarks

    def checkrevformat(self, revstr, mapname='splicemap'):
        """ git revision string is a 40 byte hex """
        self.checkhexformat(revstr, mapname)