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, includeMagic=1, \
  13                         includeSingle=1, includeDouble=1):
  14     """Return list of auto-completion options for command.
  15
  16     The list of options will be based on the locals namespace."""
  17
  18     # Get the proper chunk of code from the command.
  19     root = getRoot(command, terminator='.')
  20     try:
  21         object = eval(root, locals)
  22         attributes = getAttributeNames(object, includeMagic, \
  23                                        includeSingle, includeDouble)
  24         return attributes
  25     except:
  26         return []
  27
  28 def getAttributeNames(object, includeMagic=1, includeSingle=1, includeDouble=1):
  29     """Return list of unique attributes, including inherited, for an object."""
  30     attributes = []
  31     dict = {}
  32     if includeMagic:
  33         try: attributes += object._getAttributeNames()
  34         except: pass
  35     # Get all attribute names, removing duplicates from the attribute list.
  36     for item in getAllAttributeNames(object):
  37         dict[item] = None
  38     attributes += dict.keys()
  39     attributes.sort()
  40     if not includeSingle:
  41         attributes = filter(lambda item: item[0]!='_' or item[1]=='_', attributes)
  42     if not includeDouble:
  43         attributes = filter(lambda item: item[:2]!='__', attributes)
  44     return attributes
  45
  46 def getAllAttributeNames(object):
  47     """Return list of all attributes, including inherited, for an object.
  48
  49     Recursively walk through a class and all base classes.
  50     """
  51     attributes = []
  52     # Wake up sleepy objects - a hack for ZODB objects in "ghost" state.
  53     wakeupcall = dir(object)
  54     del wakeupcall
  55     # Get attributes available through the normal convention.
  56     attributes += dir(object)
  57     # For a class instance, get the attributes for the class.
  58     if hasattr(object, '__class__'):
  59         # Break a circular reference. This happens with extension classes.
  60         if object.__class__ is object:
  61             pass
  62         else:
  63             attributes += getAllAttributeNames(object.__class__)
  64     # Also get attributes from any and all parent classes.
  65     if hasattr(object, '__bases__'):
  66         for base in object.__bases__:
  67             attributes += getAllAttributeNames(base)
  68     return attributes
  69
  70 def getCallTip(command='', locals=None):
  71     """Return call tip text for a command.
  72
  73     The call tip information will be based on the locals namespace."""
  74
  75     # Get the proper chunk of code from the command.
  76     root = getRoot(command, terminator='(')
  77     try:
  78         object = eval(root, locals)
  79     except:
  80         return ''
  81     dropSelf = 0
  82     if hasattr(object, '__name__'):  # Make sure this is a useable object.
  83         # Switch to the object that has the information we need.
  84         if inspect.ismethod(object) or hasattr(object, 'im_func'):
  85             # Get the function from the object otherwise inspect.getargspec()
  86             # complains that the object isn't a Python function.
  87             object = object.im_func
  88             dropSelf = 1
  89         elif inspect.isclass(object):
  90             # Get the __init__ method function for the class.
  91             try:
  92                 object = object.__init__.im_func
  93                 dropSelf = 1
  94             except AttributeError:
  95                 for base in object.__bases__:
  96                     constructor = _find_constructor(base)
  97                     if constructor is not None:
  98                         object = constructor
  99                         dropSelf = 1
 100                         break
 101         name = object.__name__
 102         tip1 = ''
 103         if inspect.isbuiltin(object):
 104             # Builtin functions don't have an argspec that we can get.
 105             pass
 106         elif inspect.isfunction(object):
 107             # tip1 is a string like: "getCallTip(command='', locals=None)"
 108             argspec = apply(inspect.formatargspec, inspect.getargspec(object))
 109             if dropSelf:
 110                 # The first parameter to a method is a reference to the
 111                 # instance, usually coded as "self", and is passed
 112                 # automatically by Python and therefore we want to drop it.
 113                 temp = argspec.split(',')
 114                 if len(temp) == 1:  # No other arguments.
 115                     argspec = '()'
 116                 else:  # Drop the first argument.
 117                     argspec = '(' + ','.join(temp[1:]).lstrip()
 118             tip1 = name + argspec
 119         doc = inspect.getdoc(object)
 120         if doc:
 121             # tip2 is the first separated line of the docstring, like:
 122             # "Return call tip text for a command."
 123             # tip3 is the rest of the docstring, like:
 124             # "The call tip information will be based on ... <snip>
 125             docpieces = doc.split('\n\n')
 126             tip2 = docpieces[0]
 127             tip3 = '\n\n'.join(docpieces[1:])
 128             tip = '%s\n\n%s\n\n%s' % (tip1, tip2, tip3)
 129         else:
 130             tip = tip1
 131         return tip.strip()
 132     else:
 133         return ''
 134
 135 def getRoot(command, terminator=None):
 136     """Return the rightmost root portion of an arbitrary Python command.
 137
 138     The command would normally terminate with a "(" or ".". Anything after
 139     the terminator will be dropped, allowing you to get back to the root.
 140     Return only the root portion that can be eval()'d without side effects.
 141     """
 142     root = ''
 143     validChars = "._" + string.uppercase + string.lowercase + string.digits
 144     if terminator:
 145         # Drop the final terminator and anything that follows.
 146         pieces = command.split(terminator)
 147         if len(pieces) > 1:
 148             command = terminator.join(pieces[:-1])
 149     if len(command) == 0:
 150         root = ''
 151     elif command in ("''", '""', '""""""', '[]', '()', '{}'):
 152         # Let empty type delimiter pairs go through.
 153         root = command
 154     else:
 155         # Go backward through the command until we hit an "invalid" character.
 156         i = len(command)
 157         while i and command[i-1] in validChars:
 158             i -= 1
 159         # Detect situations where we are in the middle of a string.
 160         # This code catches the simplest case, but needs to catch others.
 161         if command[i-1] in ("'", '"'):
 162             # We're in the middle of a string so we aren't dealing with an
 163             # object and it would be misleading to return anything here.
 164             root = ''
 165         else:
 166             # Grab everything from the "invalid" character to the end.
 167             root = command[i:]
 168     return root
 169
 170