source: tracdarcs/tracdarcs/command.py @ 107

# -*- coding: iso-8859-1 -*-
#
# Copyright (C) 2005 Edgewall Software
# Copyright (C) 2006 K.S.Sreeram <sreeram@tachyontech.net>
# Copyright (C) 2007,2008 Lele Gaifax <lele@metapensiero.it>
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at http://trac.edgewall.com/license.html.
#
# This software consists of voluntary contributions made by many
# individuals. For the exact contribution history, see the revision
# history and logs, available at http://projects.edgewall.com/trac/.
#
# Author: K.S.Sreeram <sreeram@tachyontech.net>

import sys, os, StringIO
from trac.util import TracError, NaivePopen
import ann2ascii

class DarcsCommand(object):
    '''
    A simple wrapper around the 'darcs' command.
    '''
    def __init__(self, darcs_bin, repo_dir, log=None):
        self.darcs_bin = darcs_bin
        self.repo_dir = repo_dir
        self.log = log
        self.darcs_version = self._run('--version').strip()
        if self.log:
            self.log.info('Using %s, version %s',
                          self.darcs_bin, self.darcs_version)

    def _run(self, command, input=None):
        ''' Run the darcs command 'command', and return the output'''
        if sys.platform == 'win32':
            command = 'cd %s & set TZ=UTC & %s %s' % (self.repo_dir,
                                                      self.darcs_bin,
                                                      command)
        else:
            command = 'cd %s; TZ=UTC %s %s' % (self.repo_dir,
                                               self.darcs_bin,
                                               command)
        if self.log:
            self.log.debug(command)
        np = NaivePopen(command, input=input, capturestderr=True)
        if np.errorlevel:
            err = 'Running (%s) failed: %s, %s: %s' % (command,
                    np.errorlevel,np.err,np.out)
            raise TracError(err, title='Darcs execution failed')
        return np.out

    def changes(self, from_hash=None):
        '''
        Returns all changes since patch 'from_hash'. If 'from_hash'
        is None, then all changes are returned. The changes are
        ordered from oldest to latest.
        '''
        cmd = 'changes --xml-output --reverse --summary'
        if from_hash is not None:
            cmd += ' --from-match "hash %s"' % from_hash
        return self._run(cmd)

    def annotate(self, hash, path):
        '''
        This is used to feed ann2ascii.py to get the contents of
        file 'path', as of patch 'hash'.
        '''
        cmd = 'annotate --xml-output --match "hash %s" %s'
        cmd = cmd % (hash,path)
        return self._run(cmd)

    def simulate_cat(self, hash, path, cat_cmd):
        # This is an ugly hack to simulate 'darcs query contents' on darcs 1.0.
        # We basically do a 'darcs diff' giving 'cat %2'
        # as the diff command!!
        # When using --diff-command, darcs prints:
        #  Running command <blah blah>...
        #  Hit return to move on...
        # So we need to pass a dummy '\n' as input to the command
        # and remove the prompt messages from the output.
        cmd = 'diff --diff-command "%s %%2"' % cat_cmd
        cmd += ' --to-match "hash %s" "%s"' % (hash,path)
        data = self._run(cmd, input='\n')
        # Remove cruft added by darcs...
        marker = 'Hit return to move on...'
        pos = data.find(marker)
        data = data[pos+len(marker):]
        # Remove extra newline at the end
        if data.endswith('\r\n'):
            data = data[:-2]
        elif data.endswith('\n'):
            data = data[:-1]
        return data

    def cat(self, hash, path):
        if self.darcs_version >= '2.0':
            return self._run('query contents --quiet --match "hash %s" "%s"' %
                             (hash, path))
        elif sys.platform == 'win32':
            # see if cygwin's cat is available
            # if yes then use 'simulate_cat'
            # else use annotate
            cygwin_cat = r'c:\cygwin\bin\cat.exe'
            if os.path.isfile(cygwin_cat):
                return self.simulate_cat(hash, path, cat_cmd=cygwin_cat)
            annotate = self.annotate(hash, self.path)
            ann = ann2ascii.parse_annotate(StringIO.StringIO(annotate))
            out = StringIO.StringIO()
            ann.write(out)
            return out.getvalue()
        else:
            return self.simulate_cat(hash, path, cat_cmd='cat')