'''

kwutil provides required little helpers for the Mercurial

keyword extension and the Python pretxncommit hook pretxnkw.

'''

from mercurial import util

import os.path

# supported keywords for use in regexes

hgkeywords = 'Id|Header|Author|Date|Revision|RCSFile|Source'

def kwexpand(matchobj, repo, Revision, f, date, Author):

    '''Called by keyword extension and pretxnkw pretxncomit hook,

    sets supported keywords as local variables and evaluates them

    to their expansion if matchobj is equal to their string

    representation.'''

    RCSFile = os.path.basename(f)+',v'

    Source = os.path.join(repo.root, f)+',v'

    Date = util.datestr(date)

    revdateauth = '%s %s %s' % (Revision,

            util.datestr(date=date, format=util.defaultdateformats[0]),

                                                # %Y-%m-%d %H:%M:%S

            util.shortuser(Author))

    Header = '%s %s' % (Source, revdateauth)

    Id = '%s %s' % (RCSFile, revdateauth)

    return '$%s: %s $' % (matchobj.group(1), eval(matchobj.group(1)))