Source Code for Module osh.command.help

  1  # osh 
  2  # Copyright (C) Jack Orenstein <jao@geophile.com> 
  3  # 
  4  # This program is free software; you can redistribute it and/or modify 
  5  # it under the terms of the GNU General Public License as published by 
  6  # the Free Software Foundation; either version 2 of the License, or 
  7  # (at your option) any later version. 
  8  # 
  9  # This program is distributed in the hope that it will be useful, 
 10  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
 11  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 12  # GNU General Public License for more details. 
 13  # 
 14  # You should have received a copy of the GNU General Public License 
 15  # along with this program; if not, write to the Free Software 
 16  # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
 17   
 18  """C{help [OSH_COMMAND]} 
 19   
 20  If C{OSH_COMMAND} is specified, print usage information for the named osh command. Otherwise, list 
 21  the builtin commands. 
 22  """ 
 23   
 24  import sys 
 25   
 26  import osh.core 
 27   
 28  # CLI 
 29 -def _help(): 
 30      return _Help() 
 31   
 32  # API 
 33 -def help(osh_command = None): 
 34      """Prints usage information on osh commands. If C{osh_command} is specified, 
 35      print usage information for the named osh command. Otherwise, list the builtin commands. 
 36      """ 
 37      return _Help() 
 38   
 39 -class _Help(osh.core.Generator): 
 40   
 41      _command_name = None 
 42   
 43   
 44      # object interface 
 45   
 46 -    def __init__(self): 
 47          osh.core.Generator.__init__(self, '', (0, 1)) 
 48   
 49   
 50      # OshCommand interface 
 51       
 52 -    def doc(self): 
 53          return __doc__ 
 54   
 55 -    def setup(self): 
 56          args = self.args() 
 57          if args.has_next(): 
 58              self._command_name = args.next_string() 
 59              if args.has_next(): 
 60                  self.usage() 
 61   
 62      # Generator interface 
 63       
 64 -    def execute(self): 
 65          if self._command_name: 
 66              try: 
 67                  top_level_module = __import__('osh.command.' + self._command_name) 
 68                  module = getattr(top_level_module, 'command') 
 69                  module = getattr(module, self._command_name) 
 70                  print _remove_epydoc_markup(module.__doc__) 
 71              except Exception, e: 
 72                  print >>sys.stderr, "Can't find documentation for %s: %s" % (self._command_name, e) 
 73          else: 
 74              import osh.command 
 75              import osh.command.help 
 76              print _remove_epydoc_markup(__doc__) 
 77              print 'Builtin commands:' 
 78              for command in osh.command.cli: 
 79                  print '\t', command 
 80   
 81  # Translation of epydoc markup to plain text. This is pretty weak -- it doesn't 
 82  # account for nested markup or markup inside quotes. 
 83   
 84  _MARKUP = ['B{', 'C{', 'i{', '::'] 
 85   
 86 -def _nearest_markup(text, start): 
 87      nearest_markup = None 
 88      nearest_start = len(text) 
 89      for i in xrange(len(_MARKUP)): 
 90          markup = _MARKUP[i] 
 91          position = text.find(markup, start) 
 92          if position != -1 and position < nearest_start: 
 93              nearest_markup = markup 
 94              nearest_start = position 
 95      if nearest_markup: 
 96          if '{' in nearest_markup: 
 97              markup_end = text.find('}', nearest_start) 
 98              assert markup_end > nearest_start 
 99          else: 
100              markup_end = None 
101          return nearest_start, nearest_markup, markup_end 
102      else: 
103          return None, None, None 
104   
105 -def _remove_epydoc_markup(text): 
106      plain = [] 
107      plain_start = 0 
108      while plain_start < len(text): 
109          markup_start, markup, markup_end = _nearest_markup(text, plain_start) 
110          if markup_start is None: 
111              # No more markup 
112              plain.append(text[plain_start :]) 
113              plain_start = len(text) 
114          else: 
115              # Get everything up to markup 
116              plain.append(text[plain_start : markup_start]) 
117              if '{' in markup: 
118                  # If markup is x{...} get text between the braces. 
119                  assert markup_end is not None, markup_end 
120                  plain.append(text[markup_start + len(markup) : markup_end]) 
121                  plain_start = markup_end + 1 
122              else: # must be :: 
123                  plain.append(':') 
124                  plain_start = markup_start + len(markup)             
125      return ''.join(plain) 
126