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