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 __version__ = "$Revision$"[11:-2]
   7
   8 import inspect
   9 import string
  10
  11 def getAutoCompleteList(command='', locals=None, includeMagic=1, \
  12                         includeSingle=1, includeDouble=1):
  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 = getAttributeNames(object, includeMagic, \
  22                                        includeSingle, includeDouble)
  23         return attributes
  24     except:
  25         return []
  26
  27 def getAttributeNames(object, includeMagic=1, includeSingle=1, includeDouble=1):
  28     """Return list of unique attributes, including inherited, for an object."""
  29     attributes = []
  30     dict = {}
  31     if includeMagic:
  32         try: attributes += object._getAttributeNames()
  33         except: pass
  34     # Get all attribute names, removing duplicates from the attribute list.
  35     for item in getAllAttributeNames(object):
  36         dict[item] = None
  37     attributes += dict.keys()
  38     attributes.sort(lambda x, y: cmp(x.lower(), y.lower()))
  39     if not includeSingle:
  40         attributes = filter(lambda item: item[0]!='_' or item[1]=='_', attributes)
  41     if not includeDouble:
  42         attributes = filter(lambda item: item[:2]!='__', attributes)
  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     # Wake up sleepy objects - a hack for ZODB objects in "ghost" state.
  52     wakeupcall = dir(object)
  53     del wakeupcall
  54     # Get attributes available through the normal convention.
  55     attributes += dir(object)
  56     # For a class instance, get the attributes for the class.
  57     if hasattr(object, '__class__'):
  58         # Break a circular reference. This happens with extension classes.
  59         if object.__class__ is object:
  60             pass
  61         else:
  62             attributes += getAllAttributeNames(object.__class__)
  63     # Also get attributes from any and all parent classes.
  64     if hasattr(object, '__bases__'):
  65         for base in object.__bases__:
  66             attributes += getAllAttributeNames(base)
  67     return attributes
  68
  69 def getCallTip(command='', locals=None):
  70     """Return call tip text for a command.
  71
  72     The call tip information will be based on the locals namespace."""
  73
  74     # Get the proper chunk of code from the command.
  75     root = getRoot(command, terminator='(')
  76     try:
  77         object = eval(root, locals)
  78     except:
  79         return ''
  80     dropSelf = 0
  81     if hasattr(object, '__name__'):  # Make sure this is a useable object.
  82         # Switch to the object that has the information we need.
  83         if inspect.ismethod(object) or hasattr(object, 'im_func'):
  84             # Get the function from the object otherwise inspect.getargspec()
  85             # complains that the object isn't a Python function.
  86             object = object.im_func
  87             dropSelf = 1
  88         elif inspect.isclass(object):
  89             # Get the __init__ method function for the class.
  90             try:
  91                 object = object.__init__.im_func
  92                 dropSelf = 1
  93             except AttributeError:
  94                 for base in object.__bases__:
  95                     constructor = _find_constructor(base)
  96                     if constructor is not None:
  97                         object = constructor
  98                         dropSelf = 1
  99                         break
 100         name = object.__name__
 101         tip1 = ''
 102         if inspect.isbuiltin(object):
 103             # Builtin functions don't have an argspec that we can get.
 104             pass
 105         elif inspect.isfunction(object):
 106             # tip1 is a string like: "getCallTip(command='', locals=None)"
 107             argspec = apply(inspect.formatargspec, inspect.getargspec(object))
 108             if dropSelf:
 109                 # The first parameter to a method is a reference to the
 110                 # instance, usually coded as "self", and is passed
 111                 # automatically by Python and therefore we want to drop it.
 112                 temp = argspec.split(',')
 113                 if len(temp) == 1:  # No other arguments.
 114                     argspec = '()'
 115                 else:  # Drop the first argument.
 116                     argspec = '(' + ','.join(temp[1:]).lstrip()
 117             tip1 = name + argspec
 118         doc = inspect.getdoc(object)
 119         if doc:
 120             # tip2 is the first separated line of the docstring, like:
 121             # "Return call tip text for a command."
 122             # tip3 is the rest of the docstring, like:
 123             # "The call tip information will be based on ... <snip>
 124             docpieces = doc.split('\n\n')
 125             tip2 = docpieces[0]
 126             tip3 = '\n\n'.join(docpieces[1:])
 127             tip = '%s\n\n%s\n\n%s' % (tip1, tip2, tip3)
 128         else:
 129             tip = tip1
 130         return tip.strip()
 131     else:
 132         return ''
 133
 134 def getRoot(command, terminator=None):
 135     """Return the rightmost root portion of an arbitrary Python command.
 136
 137     The command would normally terminate with a "(" or ".". Anything after
 138     the terminator will be dropped, allowing you to get back to the root.
 139     Return only the root portion that can be eval()'d without side effects.
 140     """
 141     root = ''
 142     validChars = "._" + string.uppercase + string.lowercase + string.digits
 143     if terminator:
 144         # Drop the final terminator and anything that follows.
 145         pieces = command.split(terminator)
 146         if len(pieces) > 1:
 147             command = terminator.join(pieces[:-1])
 148     if len(command) == 0:
 149         root = ''
 150     elif command in ("''", '""', '""""""', '[]', '()', '{}'):
 151         # Let empty type delimiter pairs go through.
 152         root = command
 153     else:
 154         # Go backward through the command until we hit an "invalid" character.
 155         i = len(command)
 156         while i and command[i-1] in validChars:
 157             i -= 1
 158         # Detect situations where we are in the middle of a string.
 159         # This code catches the simplest case, but needs to catch others.
 160         if command[i-1] in ("'", '"'):
 161             # We're in the middle of a string so we aren't dealing with an
 162             # object and it would be misleading to return anything here.
 163             root = ''
 164         else:
 165             # Grab everything from the "invalid" character to the end.
 166             root = command[i:]
 167     return root
 168
 169
 170