~bzr-pqm/bzr/bzr.dev : contents of bzrlib/commands.py at revision 282

~bzr-pqm/bzr/bzr.dev : (revision 282)
# Copyright (C) 2004, 2005 by Martin Pool
# Copyright (C) 2005 by Canonical Ltd


# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

# 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

"""Bazaar-NG -- a free distributed version-control tool
http://bazaar-ng.org/

**WARNING: THIS IS AN UNSTABLE DEVELOPMENT VERSION**

* Metadata format is not stable yet -- you may need to
  discard history in the future.

* Many commands unimplemented or partially implemented.

* Space-inefficient storage.

* No merge operators yet.

Interesting commands:

  bzr help [COMMAND]
      Show help screen
  bzr version
      Show software version/licence/non-warranty.
  bzr init
      Start versioning the current directory
  bzr add FILE...
      Make files versioned.
  bzr log
      Show revision history.
  bzr rename FROM TO
      Rename one file.
  bzr move FROM... DESTDIR
      Move one or more files to a different directory.
  bzr diff [FILE...]
      Show changes from last revision to working copy.
  bzr commit -m 'MESSAGE'
      Store current state as new revision.
  bzr export REVNO DESTINATION
      Export the branch state at a previous version.
  bzr status
      Show summary of pending changes.
  bzr remove FILE...
      Make a file not versioned.
  bzr info
      Show statistics about this branch.
  bzr check
      Verify history is stored safely. 
  (for more type 'bzr help commands')
"""




import sys, os, time, types, shutil, tempfile, fnmatch, difflib, os.path
from sets import Set
from pprint import pprint
from stat import *
from glob import glob
from inspect import getdoc

import bzrlib
from bzrlib.store import ImmutableStore
from bzrlib.trace import mutter, note, log_error
from bzrlib.errors import bailout, BzrError, BzrCheckError
from bzrlib.osutils import quotefn, pumpfile, isdir, isfile
from bzrlib.tree import RevisionTree, EmptyTree, WorkingTree, Tree
from bzrlib.revision import Revision
from bzrlib import Branch, Inventory, InventoryEntry, ScratchBranch, BZRDIR, \
     format_date

BZR_DIFF_FORMAT = "## Bazaar-NG diff, format 0 ##\n"
BZR_PATCHNAME_FORMAT = 'cset:sha1:%s'

## standard representation
NONE_STRING = '(none)'
EMPTY = 'empty'


## TODO: Perhaps a different version of inventory commands that
## returns iterators...

## TODO: Perhaps an AtomicFile class that writes to a temporary file and then renames.

## TODO: Some kind of locking on branches.  Perhaps there should be a
## parameter to the branch object saying whether we want a read or
## write lock; release it from destructor.  Perhaps don't even need a
## read lock to look at immutable objects?

## TODO: Perhaps make UUIDs predictable in test mode to make it easier
## to compare output?

## TODO: Some kind of global code to generate the right Branch object
## to work on.  Almost, but not quite all, commands need one, and it
## can be taken either from their parameters or their working
## directory.

## TODO: rename command, needed soon: check destination doesn't exist
## either in working copy or tree; move working copy; update
## inventory; write out

## TODO: move command; check destination is a directory and will not
## clash; move it.

## TODO: command to show renames, one per line, as to->from



cmd_aliases = {
    '?':         'help',
    'ci':        'commit',
    'checkin':   'commit',
    'di':        'diff',
    'st':        'status',
    'stat':      'status',
    }


def get_cmd_handler(cmd):
    cmd = str(cmd)
    
    cmd = cmd_aliases.get(cmd, cmd)
    
    try:
        cmd_handler = globals()['cmd_' + cmd.replace('-', '_')]
    except KeyError:
        raise BzrError("unknown command %r" % cmd)

    return cmd, cmd_handler



def cmd_status(all=False):
    """Display status summary.

    For each file there is a single line giving its file state and name.
    The name is that in the current revision unless it is deleted or
    missing, in which case the old name is shown.
    """
    #import bzrlib.status
    #bzrlib.status.tree_status(Branch('.'))
    Branch('.').show_status(show_all=all)



######################################################################
# examining history
def cmd_get_revision(revision_id):
    Branch('.').get_revision(revision_id).write_xml(sys.stdout)


def cmd_get_file_text(text_id):
    """Get contents of a file by hash."""
    sf = Branch('.').text_store[text_id]
    pumpfile(sf, sys.stdout)



######################################################################
# commands
    

def cmd_revno():
    """Show number of revisions on this branch"""
    print Branch('.').revno()
    

    
def cmd_add(file_list, verbose=False):
    """Add specified files or directories.

    In non-recursive mode, all the named items are added, regardless
    of whether they were previously ignored.  A warning is given if
    any of the named files are already versioned.

    In recursive mode (the default), files are treated the same way
    but the behaviour for directories is different.  Directories that
    are already versioned do not give a warning.  All directories,
    whether already versioned or not, are searched for files or
    subdirectories that are neither versioned or ignored, and these
    are added.  This search proceeds recursively into versioned
    directories.

    Therefore simply saying 'bzr add .' will version all files that
    are currently unknown.

    TODO: Perhaps adding a file whose directly is not versioned should
    recursively add that parent, rather than giving an error?
    """
    bzrlib.add.smart_add(file_list, verbose)
    

def cmd_relpath(filename):
    """Show path of file relative to root"""
    print Branch(filename).relpath(filename)



def cmd_inventory(revision=None):
    """Show inventory of the current working copy."""
    ## TODO: Also optionally show a previous inventory
    ## TODO: Format options
    b = Branch('.')
    if revision == None:
        inv = b.read_working_inventory()
    else:
        inv = b.get_revision_inventory(b.lookup_revision(revision))
        
    for path, entry in inv.iter_entries():
        print '%-50s %s' % (entry.file_id, path)



# TODO: Maybe a 'mv' command that has the combined move/rename
# special behaviour of Unix?

def cmd_move(source_list, dest):
    b = Branch('.')

    b.move([b.relpath(s) for s in source_list], b.relpath(dest))



def cmd_rename(from_name, to_name):
    """Change the name of an entry.

    usage: bzr rename FROM_NAME TO_NAME

    examples:
      bzr rename frob.c frobber.c
      bzr rename src/frob.c lib/frob.c

    It is an error if the destination name exists.

    See also the 'move' command, which moves files into a different
    directory without changing their name.

    TODO: Some way to rename multiple files without invoking bzr for each
    one?"""
    b = Branch('.')
    b.rename_one(b.relpath(from_name), b.relpath(to_name))
    



def cmd_renames(dir='.'):
    """Show list of renamed files.

    usage: bzr renames [BRANCH]

    TODO: Option to show renames between two historical versions.

    TODO: Only show renames under dir, rather than in the whole branch.
    """
    b = Branch(dir)
    old_inv = b.basis_tree().inventory
    new_inv = b.read_working_inventory()
    
    renames = list(bzrlib.tree.find_renames(old_inv, new_inv))
    renames.sort()
    for old_name, new_name in renames:
        print "%s => %s" % (old_name, new_name)        



def cmd_info():
    """info: Show statistical information for this branch

    usage: bzr info"""
    import info
    info.show_info(Branch('.'))        
    


def cmd_remove(file_list, verbose=False):
    b = Branch(file_list[0])
    b.remove([b.relpath(f) for f in file_list], verbose=verbose)



def cmd_file_id(filename):
    """Print file_id of a particular file or directory.

    usage: bzr file-id FILE

    The file_id is assigned when the file is first added and remains the
    same through all revisions where the file exists, even when it is
    moved or renamed.
    """
    b = Branch(filename)
    i = b.inventory.path2id(b.relpath(filename))
    if i == None:
        bailout("%r is not a versioned file" % filename)
    else:
        print i


def cmd_file_id_path(filename):
    """Print path of file_ids to a file or directory.

    usage: bzr file-id-path FILE

    This prints one line for each directory down to the target,
    starting at the branch root."""
    b = Branch(filename)
    inv = b.inventory
    fid = inv.path2id(b.relpath(filename))
    if fid == None:
        bailout("%r is not a versioned file" % filename)
    for fip in inv.get_idpath(fid):
        print fip


def cmd_revision_history():
    for patchid in Branch('.').revision_history():
        print patchid


def cmd_directories():
    for name, ie in Branch('.').read_working_inventory().directories():
        if name == '':
            print '.'
        else:
            print name


def cmd_missing():
    for name, ie in Branch('.').working_tree().missing():
        print name


def cmd_init():
    # TODO: Check we're not already in a working directory?  At the
    # moment you'll get an ugly error.
    
    # TODO: What if we're in a subdirectory of a branch?  Would like
    # to allow that, but then the parent may need to understand that
    # the children have disappeared, or should they be versioned in
    # both?

    # TODO: Take an argument/option for branch name.
    Branch('.', init=True)


def cmd_diff(revision=None, file_list=None):
    """bzr diff: Show differences in working tree.
    
    usage: bzr diff [-r REV] [FILE...]

    --revision REV
         Show changes since REV, rather than predecessor.

    If files are listed, only the changes in those files are listed.
    Otherwise, all changes for the tree are listed.

    TODO: Given two revision arguments, show the difference between them.

    TODO: Allow diff across branches.

    TODO: Option to use external diff command; could be GNU diff, wdiff,
          or a graphical diff.

    TODO: Python difflib is not exactly the same as unidiff; should
          either fix it up or prefer to use an external diff.

    TODO: If a directory is given, diff everything under that.

    TODO: Selected-file diff is inefficient and doesn't show you
          deleted files.

    TODO: This probably handles non-Unix newlines poorly.
"""

    ## TODO: Shouldn't be in the cmd function.

    b = Branch('.')

    if revision == None:
        old_tree = b.basis_tree()
    else:
        old_tree = b.revision_tree(b.lookup_revision(revision))
        
    new_tree = b.working_tree()

    # TODO: Options to control putting on a prefix or suffix, perhaps as a format string
    old_label = ''
    new_label = ''

    DEVNULL = '/dev/null'
    # Windows users, don't panic about this filename -- it is a
    # special signal to GNU patch that the file should be created or
    # deleted respectively.

    # TODO: Generation of pseudo-diffs for added/deleted files could
    # be usefully made into a much faster special case.

    # TODO: Better to return them in sorted order I think.

    if file_list:
        file_list = [b.relpath(f) for f in file_list]

    # FIXME: If given a file list, compare only those files rather
    # than comparing everything and then throwing stuff away.
    
    for file_state, fid, old_name, new_name, kind in bzrlib.diff_trees(old_tree, new_tree):

        if file_list and (new_name not in file_list):
            continue
        
        # Don't show this by default; maybe do it if an option is passed
        # idlabel = '      {%s}' % fid
        idlabel = ''

        # FIXME: Something about the diff format makes patch unhappy
        # with newly-added files.

        def diffit(oldlines, newlines, **kw):
            
            # FIXME: difflib is wrong if there is no trailing newline.
            # The syntax used by patch seems to be "\ No newline at
            # end of file" following the last diff line from that
            # file.  This is not trivial to insert into the
            # unified_diff output and it might be better to just fix
            # or replace that function.

            # In the meantime we at least make sure the patch isn't
            # mangled.
            

            # Special workaround for Python2.3, where difflib fails if
            # both sequences are empty.
            if not oldlines and not newlines:
                return

            nonl = False

            if oldlines and (oldlines[-1][-1] != '\n'):
                oldlines[-1] += '\n'
                nonl = True
            if newlines and (newlines[-1][-1] != '\n'):
                newlines[-1] += '\n'
                nonl = True

            ud = difflib.unified_diff(oldlines, newlines, **kw)
            sys.stdout.writelines(ud)
            if nonl:
                print "\\ No newline at end of file"
            sys.stdout.write('\n')
        
        if file_state in ['.', '?', 'I']:
            continue
        elif file_state == 'A':
            print '*** added %s %r' % (kind, new_name)
            if kind == 'file':
                diffit([],
                       new_tree.get_file(fid).readlines(),
                       fromfile=DEVNULL,
                       tofile=new_label + new_name + idlabel)
        elif file_state == 'D':
            assert isinstance(old_name, types.StringTypes)
            print '*** deleted %s %r' % (kind, old_name)
            if kind == 'file':
                diffit(old_tree.get_file(fid).readlines(), [],
                       fromfile=old_label + old_name + idlabel,
                       tofile=DEVNULL)
        elif file_state in ['M', 'R']:
            if file_state == 'M':
                assert kind == 'file'
                assert old_name == new_name
                print '*** modified %s %r' % (kind, new_name)
            elif file_state == 'R':
                print '*** renamed %s %r => %r' % (kind, old_name, new_name)

            if kind == 'file':
                diffit(old_tree.get_file(fid).readlines(),
                       new_tree.get_file(fid).readlines(),
                       fromfile=old_label + old_name + idlabel,
                       tofile=new_label + new_name)
        else:
            bailout("can't represent state %s {%s}" % (file_state, fid))



def cmd_deleted(show_ids=False):
    """List files deleted in the working tree.

    TODO: Show files deleted since a previous revision, or between two revisions.
    """
    b = Branch('.')
    old = b.basis_tree()
    new = b.working_tree()

    ## TODO: Much more efficient way to do this: read in new
    ## directories with readdir, rather than stating each one.  Same
    ## level of effort but possibly much less IO.  (Or possibly not,
    ## if the directories are very large...)

    for path, ie in old.inventory.iter_entries():
        if not new.has_id(ie.file_id):
            if show_ids:
                print '%-50s %s' % (path, ie.file_id)
            else:
                print path



def cmd_parse_inventory():
    import cElementTree
    
    cElementTree.ElementTree().parse(file('.bzr/inventory'))



def cmd_load_inventory():
    """Load inventory for timing purposes"""
    Branch('.').basis_tree().inventory


def cmd_dump_inventory():
    Branch('.').read_working_inventory().write_xml(sys.stdout)


def cmd_dump_new_inventory():
    import bzrlib.newinventory
    inv = Branch('.').basis_tree().inventory
    bzrlib.newinventory.write_inventory(inv, sys.stdout)


def cmd_load_new_inventory():
    import bzrlib.newinventory
    bzrlib.newinventory.read_new_inventory(sys.stdin)
                
    
def cmd_dump_slacker_inventory():
    import bzrlib.newinventory
    inv = Branch('.').basis_tree().inventory
    bzrlib.newinventory.write_slacker_inventory(inv, sys.stdout)



def cmd_dump_text_inventory():
    import bzrlib.textinv
    inv = Branch('.').basis_tree().inventory
    bzrlib.textinv.write_text_inventory(inv, sys.stdout)


def cmd_load_text_inventory():
    import bzrlib.textinv
    inv = bzrlib.textinv.read_text_inventory(sys.stdin)
    print 'loaded %d entries' % len(inv)
    
    

def cmd_root(filename=None):
    """Print the branch root."""
    print bzrlib.branch.find_branch_root(filename)
    

def cmd_log(timezone='original', verbose=False):
    """Show log of this branch.

    TODO: Options for utc; to show ids; to limit range; etc.
    """
    Branch('.').write_log(show_timezone=timezone, verbose=verbose)


def cmd_ls(revision=None, verbose=False):
    """List files in a tree.

    TODO: Take a revision or remote path and list that tree instead.
    """
    b = Branch('.')
    if revision == None:
        tree = b.working_tree()
    else:
        tree = b.revision_tree(b.lookup_revision(revision))
        
    for fp, fc, kind, fid in tree.list_files():
        if verbose:
            if kind == 'directory':
                kindch = '/'
            elif kind == 'file':
                kindch = ''
            else:
                kindch = '???'
                
            print '%-8s %s%s' % (fc, fp, kindch)
        else:
            print fp
    
    

def cmd_unknowns():
    """List unknown files"""
    for f in Branch('.').unknowns():
        print quotefn(f)



def cmd_ignored():
    """List ignored files and the patterns that matched them.
      """
    tree = Branch('.').working_tree()
    for path, file_class, kind, file_id in tree.list_files():
        if file_class != 'I':
            continue
        ## XXX: Slightly inefficient since this was already calculated
        pat = tree.is_ignored(path)
        print '%-50s %s' % (path, pat)


def cmd_lookup_revision(revno):
    try:
        revno = int(revno)
    except ValueError:
        bailout("usage: lookup-revision REVNO",
                ["REVNO is a non-negative revision number for this branch"])

    print Branch('.').lookup_revision(revno) or NONE_STRING



def cmd_export(revno, dest):
    """Export past revision to destination directory."""
    b = Branch('.')
    rh = b.lookup_revision(int(revno))
    t = b.revision_tree(rh)
    t.export(dest)

def cmd_cat(revision, filename):
    """Print file to stdout."""
    b = Branch('.')
    b.print_file(b.relpath(filename), int(revision))


######################################################################
# internal/test commands


def cmd_uuid():
    """Print a newly-generated UUID."""
    print bzrlib.osutils.uuid()



def cmd_local_time_offset():
    print bzrlib.osutils.local_time_offset()



def cmd_commit(message=None, verbose=False):
    """Commit changes to a new revision.

    --message MESSAGE
        Description of changes in this revision; free form text.
        It is recommended that the first line be a single-sentence
        summary.
    --verbose
        Show status of changed files,

    TODO: Commit only selected files.

    TODO: Run hooks on tree to-be-committed, and after commit.

    TODO: Strict commit that fails if there are unknown or deleted files.
    """

    if not message:
        bailout("please specify a commit message")
    Branch('.').commit(message, verbose=verbose)


def cmd_check(dir='.'):
    """check: Consistency check of branch history.

    usage: bzr check [-v] [BRANCH]

    options:
      --verbose, -v         Show progress of checking.

    This command checks various invariants about the branch storage to
    detect data corruption or bzr bugs.
    """
    import bzrlib.check
    bzrlib.check.check(Branch(dir, find_root=False))


def cmd_is(pred, *rest):
    """Test whether PREDICATE is true."""
    try:
        cmd_handler = globals()['assert_' + pred.replace('-', '_')]
    except KeyError:
        bailout("unknown predicate: %s" % quotefn(pred))
        
    try:
        cmd_handler(*rest)
    except BzrCheckError:
        # by default we don't print the message so that this can
        # be used from shell scripts without producing noise
        sys.exit(1)


def cmd_whoami():
    """Show bzr user id.

    usage: bzr whoami

    TODO: Command to show only the email-address part as parsed out.
    """
    print bzrlib.osutils.username()


def cmd_gen_revision_id():
    print bzrlib.branch._gen_revision_id(time.time())


def cmd_selftest():
    """Run internal test suite"""
    ## -v, if present, is seen by doctest; the argument is just here
    ## so our parser doesn't complain

    ## TODO: --verbose option

    failures, tests = 0, 0
    
    import doctest, bzrlib.store, bzrlib.tests
    bzrlib.trace.verbose = False

    for m in bzrlib.store, bzrlib.inventory, bzrlib.branch, bzrlib.osutils, \
        bzrlib.tree, bzrlib.tests, bzrlib.commands, bzrlib.add:
        mf, mt = doctest.testmod(m)
        failures += mf
        tests += mt
        print '%-40s %3d tests' % (m.__name__, mt),
        if mf:
            print '%3d FAILED!' % mf
        else:
            print

    print '%-40s %3d tests' % ('total', tests),
    if failures:
        print '%3d FAILED!' % failures
    else:
        print



# deprecated
cmd_doctest = cmd_selftest


######################################################################
# help


def cmd_help(topic=None):
    if topic == None:
        print __doc__
    elif topic == 'commands':
        help_commands()
    else:
        # otherwise, maybe the name of a command?
        topic, cmdfn = get_cmd_handler(topic)

        doc = getdoc(cmdfn)
        if doc == None:
            bailout("sorry, no detailed help yet for %r" % topic)

        print doc


def help_commands():
    """List all commands"""
    accu = []
    for k in globals().keys():
        if k.startswith('cmd_'):
            accu.append(k[4:].replace('_','-'))
    accu.sort()
    print "bzr commands: "
    for x in accu:
        print "   " + x
    print "note: some of these commands are internal-use or obsolete"
    # TODO: Some kind of marker for internal-use commands?
    # TODO: Show aliases?
        



def cmd_version():
    print "bzr (bazaar-ng) %s" % bzrlib.__version__
    print bzrlib.__copyright__
    print "http://bazaar-ng.org/"
    print
    print \
"""bzr comes with ABSOLUTELY NO WARRANTY.  bzr is free software, and
you may use, modify and redistribute it under the terms of the GNU 
General Public License version 2 or later."""


def cmd_rocks():
    """Statement of optimism."""
    print "it sure does!"



######################################################################
# main routine


# list of all available options; the rhs can be either None for an
# option that takes no argument, or a constructor function that checks
# the type.
OPTIONS = {
    'all':                    None,
    'help':                   None,
    'message':                unicode,
    'profile':                None,
    'revision':               int,
    'show-ids':               None,
    'timezone':               str,
    'verbose':                None,
    'version':                None,
    }

SHORT_OPTIONS = {
    'm':                      'message',
    'r':                      'revision',
    'v':                      'verbose',
}

# List of options that apply to particular commands; commands not
# listed take none.
cmd_options = {
    'add':                    ['verbose'],
    'cat':                    ['revision'],
    'commit':                 ['message', 'verbose'],
    'deleted':                ['show-ids'],
    'diff':                   ['revision'],
    'inventory':              ['revision'],
    'log':                    ['timezone', 'verbose'],
    'ls':                     ['revision', 'verbose'],
    'remove':                 ['verbose'],
    'status':                 ['all'],
    }


cmd_args = {
    'add':                    ['file+'],
    'cat':                    ['filename'],
    'commit':                 [],
    'diff':                   ['file*'],
    'export':                 ['revno', 'dest'],
    'file-id':                ['filename'],
    'file-id-path':           ['filename'],
    'get-file-text':          ['text_id'],
    'get-inventory':          ['inventory_id'],
    'get-revision':           ['revision_id'],
    'get-revision-inventory': ['revision_id'],
    'help':                   ['topic?'],
    'init':                   [],
    'log':                    [],
    'lookup-revision':        ['revno'],
    'move':                   ['source$', 'dest'],
    'relpath':                ['filename'],
    'remove':                 ['file+'],
    'rename':                 ['from_name', 'to_name'],
    'renames':                ['dir?'],
    'root':                   ['filename?'],
    'status':                 [],
    }


def parse_args(argv):
    """Parse command line.
    
    Arguments and options are parsed at this level before being passed
    down to specific command handlers.  This routine knows, from a
    lookup table, something about the available options, what optargs
    they take, and which commands will accept them.

    >>> parse_args('--help'.split())
    ([], {'help': True})
    >>> parse_args('--version'.split())
    ([], {'version': True})
    >>> parse_args('status --all'.split())
    (['status'], {'all': True})
    >>> parse_args('commit --message=biter'.split())
    (['commit'], {'message': u'biter'})
    """
    args = []
    opts = {}

    # TODO: Maybe handle '--' to end options?

    while argv:
        a = argv.pop(0)
        if a[0] == '-':
            # option names must not be unicode
            a = str(a)
            optarg = None
            if a[1] == '-':
                mutter("  got option %r" % a)
                if '=' in a:
                    optname, optarg = a[2:].split('=', 1)
                else:
                    optname = a[2:]
                if optname not in OPTIONS:
                    bailout('unknown long option %r' % a)
            else:
                shortopt = a[1:]
                if shortopt not in SHORT_OPTIONS:
                    bailout('unknown short option %r' % a)
                optname = SHORT_OPTIONS[shortopt]
            
            if optname in opts:
                # XXX: Do we ever want to support this, e.g. for -r?
                bailout('repeated option %r' % a)
                
            optargfn = OPTIONS[optname]
            if optargfn:
                if optarg == None:
                    if not argv:
                        bailout('option %r needs an argument' % a)
                    else:
                        optarg = argv.pop(0)
                opts[optname] = optargfn(optarg)
            else:
                if optarg != None:
                    bailout('option %r takes no argument' % optname)
                opts[optname] = True
        else:
            args.append(a)

    return args, opts



def _match_args(cmd, args):
    """Check non-option arguments match required pattern.

    >>> _match_args('status', ['asdasdsadasd'])
    Traceback (most recent call last):
    ...
    BzrError: ("extra arguments to command status: ['asdasdsadasd']", [])
    >>> _match_args('add', ['asdasdsadasd'])
    {'file_list': ['asdasdsadasd']}
    >>> _match_args('add', 'abc def gj'.split())
    {'file_list': ['abc', 'def', 'gj']}
    """
    # match argument pattern
    argform = cmd_args.get(cmd, [])
    argdict = {}
    # TODO: Need a way to express 'cp SRC... DEST', where it matches
    # all but one.

    # step through args and argform, allowing appropriate 0-many matches
    for ap in argform:
        argname = ap[:-1]
        if ap[-1] == '?':
            if args:
                argdict[argname] = args.pop(0)
        elif ap[-1] == '*': # all remaining arguments
            if args:
                argdict[argname + '_list'] = args[:]
                args = []
            else:
                argdict[argname + '_list'] = None
        elif ap[-1] == '+':
            if not args:
                bailout("command %r needs one or more %s"
                        % (cmd, argname.upper()))
            else:
                argdict[argname + '_list'] = args[:]
                args = []
        elif ap[-1] == '$': # all but one
            if len(args) < 2:
                bailout("command %r needs one or more %s"
                        % (cmd, argname.upper()))
            argdict[argname + '_list'] = args[:-1]
            args[:-1] = []                
        else:
            # just a plain arg
            argname = ap
            if not args:
                bailout("command %r requires argument %s"
                        % (cmd, argname.upper()))
            else:
                argdict[argname] = args.pop(0)
            
    if args:
        bailout("extra arguments to command %s: %r"
                % (cmd, args))

    return argdict



def run_bzr(argv):
    """Execute a command.

    This is similar to main(), but without all the trappings for
    logging and error handling.  
    """

    argv = [a.decode(bzrlib.user_encoding) for a in argv]
    
    try:
        args, opts = parse_args(argv[1:])
        if 'help' in opts:
            # TODO: pass down other arguments in case they asked for
            # help on a command name?
            if args:
                cmd_help(args[0])
            else:
                cmd_help()
            return 0
        elif 'version' in opts:
            cmd_version()
            return 0
        cmd = str(args.pop(0))
    except IndexError:
        log_error('usage: bzr COMMAND')
        log_error('  try "bzr help"')
        return 1

    canonical_cmd, cmd_handler = get_cmd_handler(cmd)

    # global option
    if 'profile' in opts:
        profile = True
        del opts['profile']
    else:
        profile = False

    # check options are reasonable
    allowed = cmd_options.get(canonical_cmd, [])
    for oname in opts:
        if oname not in allowed:
            bailout("option %r is not allowed for command %r"
                    % (oname, cmd))

    # TODO: give an error if there are any mandatory options which are
    # not specified?  Or maybe there shouldn't be any "mandatory
    # options" (it is an oxymoron)

    # mix arguments and options into one dictionary
    cmdargs = _match_args(canonical_cmd, args)
    for k, v in opts.items():
        cmdargs[k.replace('-', '_')] = v

    if profile:
        import hotshot
        pffileno, pfname = tempfile.mkstemp()
        try:
            prof = hotshot.Profile(pfname)
            ret = prof.runcall(cmd_handler, **cmdargs) or 0
            prof.close()

            import hotshot.stats
            stats = hotshot.stats.load(pfname)
            #stats.strip_dirs()
            stats.sort_stats('time')
            ## XXX: Might like to write to stderr or the trace file instead but
            ## print_stats seems hardcoded to stdout
            stats.print_stats(20)
            
            return ret

        finally:
            os.close(pffileno)
            os.remove(pfname)
    else:
        return cmd_handler(**cmdargs) or 0



def _report_exception(e, summary):
    import traceback
    log_error('bzr: ' + summary)
    bzrlib.trace.log_exception(e)
    tb = sys.exc_info()[2]
    exinfo = traceback.extract_tb(tb)
    if exinfo:
        sys.stderr.write('  at %s:%d in %s()\n' % exinfo[-1][:3])
    sys.stderr.write('  see ~/.bzr.log for debug information\n')


def cmd_assert_fail():
    assert False, "always fails"


def main(argv):
    bzrlib.trace.create_tracefile(argv)

    try:
        try:
            ret = run_bzr(argv)
            return ret
        except BzrError, e:
            _report_exception(e, 'error: ' + e.args[0])
            if len(e.args) > 1:
                for h in e.args[1]:
                    # some explanation or hints
                    log_error('  ' + h)
            return 1
        except AssertionError, e:
            msg = 'assertion failed'
            if str(e):
                msg += ': ' + str(e)
            _report_exception(e, msg)
        except Exception, e:
            _report_exception(e, 'exception: %s' % str(e).rstrip('\n'))
            return 1
    finally:
        bzrlib.trace.close_trace()

    ## TODO: Trap AssertionError

    # TODO: Maybe nicer handling of IOError especially for broken pipe.



if __name__ == '__main__':
    sys.exit(main(sys.argv))