wxPython/wxPython/lib/PyCrust/introspect.py

   1 """Provides a variety of introspective-type support functions for things
   2 like call tips and command auto completion."""
   3
   4 __author__ = "Patrick K. O'Brien <pobrien@orbtech.com>"
   5 __cvsid__ = "$Id$"
   6 __date__ = "August 8, 2001"
   7 __version__ = "$Revision$"[11:-2]
   8
   9 import inspect
  10 import string
  11
  12 def getAutoCompleteList(command='', locals=None):
  13     """Return list of auto-completion options for command.
  14
  15     The list of options will be based on the locals namespace."""
  16
  17     # Get the proper chunk of code from the command.
  18     root = getRoot(command, terminator='.')
  19     try:
  20         object = eval(root, locals)
  21         attributes = getAttributes(object)
  22         return attributes
  23     except:
  24         return []
  25
  26 def getAttributes(object):
  27     """Return list of unique attributes, including inherited, for an object."""
  28     attributes = []
  29     dict = {}
  30     # Remove duplicates from the attribute list.
  31     for item in getAllAttributes(object):
  32         dict[item] = None
  33     attributes += dict.keys()
  34     attributes.sort()
  35     return attributes
  36
  37 def getAllAttributes(object):
  38     """Return list of all attributes, including inherited, for an object.
  39
  40     Recursively walk through a class and all base classes.
  41     """
  42     attributes = []
  43     try:
  44         attributes += dir(object)
  45         if hasattr(object, '__class__'):
  46             attributes += getAllAttributes(object.__class__)
  47         if hasattr(object, '__bases__'):
  48             for base in object.__bases__:
  49                 attributes += getAllAttributes(base)
  50     finally:
  51         return attributes
  52
  53 def getCallTip(command='', locals=None):
  54     """Return call tip text for a command.
  55
  56     The call tip information will be based on the locals namespace."""
  57
  58     # Get the proper chunk of code from the command.
  59     root = getRoot(command, terminator='(')
  60     try:
  61         object = eval(root, locals)
  62     except:
  63         return ''
  64     dropSelf = 0
  65     if hasattr(object, '__name__'):  # Make sure this is a useable object.
  66         # Switch to the object that has the information we need.
  67         if inspect.ismethod(object):
  68             # Get the function from the object otherwise inspec.getargspec()
  69             # complains that the object isn't a Python function.
  70             object = object.im_func
  71             dropSelf = 1
  72         elif inspect.isclass(object):
  73             # Get the __init__ method for the class.
  74             try:
  75                 object = object.__init__.im_func
  76                 dropSelf = 1
  77             except AttributeError:
  78                 for base in object.__bases__:
  79                     constructor = _find_constructor(base)
  80                     if constructor is not None:
  81                         object = constructor
  82                         dropSelf = 1
  83                         break
  84         name = object.__name__
  85         if inspect.isbuiltin(object):
  86             # Builtin functions don't have an argspec that we can get.
  87             tip1 = ''
  88         else:
  89             # tip1 is a string like: "getCallTip(command='', locals=None)"
  90             argspec = apply(inspect.formatargspec, inspect.getargspec(object))
  91             if dropSelf:
  92                 # The first parameter to a method is a reference to the
  93                 # instance, usually coded as "self", and is passed
  94                 # automatically by Python and therefore we want to drop it.
  95                 temp = argspec.split(',')
  96                 if len(temp) == 1:  # No other arguments.
  97                     argspec = '()'
  98                 else:  # Drop the first argument.
  99                     argspec = '(' + ','.join(temp[1:]).lstrip()
 100             tip1 = name + argspec
 101         doc = inspect.getdoc(object)
 102         if doc:
 103             # tip2 is the first separated line of the docstring, like:
 104             # "Return call tip text for a command."
 105             # tip3 is the rest of the docstring, like:
 106             # "The call tip information will be based on ... <snip>
 107             docpieces = doc.split('\n\n')
 108             tip2 = docpieces[0]
 109             tip3 = '\n\n'.join(docpieces[1:])
 110             tip = '%s\n\n%s\n\n%s' % (tip1, tip2, tip3)
 111         else:
 112             tip = tip1
 113         return tip.strip()
 114     else:
 115         return ''
 116
 117 def getRoot(command, terminator=None):
 118     """Return the rightmost root portion of an arbitrary Python command.
 119
 120     The command would normally terminate with a "(" or ".". Anything after
 121     the terminator will be dropped, allowing you to get back to the root.
 122     """
 123     root = ''
 124     validChars = "._" + string.uppercase + string.lowercase + string.digits
 125     # Remove all whitespace from the command.
 126     command = ''.join(command.split())
 127     # Deal with the terminator.
 128     if terminator:
 129         pieces = command.split(terminator)
 130         if len(pieces) > 1:
 131             # Drop the final terminator and anything that follows.
 132             command = terminator.join(pieces[:-1])
 133     # Go backward through the command until we hit an "invalid" character.
 134     i = len(command)
 135     while i and command[i-1] in validChars:
 136         i -= 1
 137     # Grab everything from the "invalid" character to the end.
 138     root = command[i:]
 139     return root
 140