Make our fixed-up getargspec a top-level function.

There was no need for this to be a method, and this way it can be used by
external code.

IPython/OInspect.py

@@ -1,610 +1,613 b''
 # -*- coding: utf-8 -*-
 """Tools for inspecting Python objects.
 
 Uses syntax highlighting for presenting the various information elements.
 
 Similar in spirit to the inspect module, but all calls take a name argument to
 reference the name under which an object is being read.
 
 $Id: OInspect.py 2843 2007-10-15 21:22:32Z fperez $
 """
 
 #*****************************************************************************
 #       Copyright (C) 2001-2004 Fernando Perez <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #*****************************************************************************
 
 from IPython import Release
 __author__  = '%s <%s>' % Release.authors['Fernando']
 __license__ = Release.license
 
 __all__ = ['Inspector','InspectColors']
 
 # stdlib modules
 import __builtin__
+import StringIO
 import inspect
 import linecache
-import string
-import StringIO
-import types
 import os
+import string
 import sys
+import types
+
 # IPython's own
 from IPython import PyColorize
 from IPython.genutils import page,indent,Term
 from IPython.Itpl import itpl
 from IPython.wildcard import list_namespace
 from IPython.ColorANSI import *
 
 #****************************************************************************
 # HACK!!! This is a crude fix for bugs in python 2.3's inspect module.  We
 # simply monkeypatch inspect with code copied from python 2.4.
 if sys.version_info[:2] == (2,3):
     from inspect import ismodule, getabsfile, modulesbyfile
     def getmodule(object):
         """Return the module an object was defined in, or None if not found."""
         if ismodule(object):
             return object
         if hasattr(object, '__module__'):
             return sys.modules.get(object.__module__)
         try:
             file = getabsfile(object)
         except TypeError:
             return None
         if file in modulesbyfile:
             return sys.modules.get(modulesbyfile[file])
         for module in sys.modules.values():
             if hasattr(module, '__file__'):
                 modulesbyfile[
                     os.path.realpath(
                             getabsfile(module))] = module.__name__
         if file in modulesbyfile:
             return sys.modules.get(modulesbyfile[file])
         main = sys.modules['__main__']
         if not hasattr(object, '__name__'):
             return None
         if hasattr(main, object.__name__):
             mainobject = getattr(main, object.__name__)
             if mainobject is object:
                 return main
         builtin = sys.modules['__builtin__']
         if hasattr(builtin, object.__name__):
             builtinobject = getattr(builtin, object.__name__)
             if builtinobject is object:
                 return builtin
 
     inspect.getmodule = getmodule
 
 #****************************************************************************
 # Builtin color schemes
 
 Colors = TermColors  # just a shorthand
 
 # Build a few color schemes
 NoColor = ColorScheme(
     'NoColor',{
     'header' : Colors.NoColor,
     'normal' : Colors.NoColor  # color off (usu. Colors.Normal)
     }  )
 
 LinuxColors = ColorScheme(
     'Linux',{
     'header' : Colors.LightRed,
     'normal' : Colors.Normal  # color off (usu. Colors.Normal)
     } )
 
 LightBGColors = ColorScheme(
     'LightBG',{
     'header' : Colors.Red,
     'normal' : Colors.Normal  # color off (usu. Colors.Normal)
     }  )
 
 # Build table of color schemes (needed by the parser)
 InspectColors = ColorSchemeTable([NoColor,LinuxColors,LightBGColors],
                                  'Linux')
 
 #****************************************************************************
 # Auxiliary functions
 def getdoc(obj):
     """Stable wrapper around inspect.getdoc.
 
     This can't crash because of attribute problems.
 
     It also attempts to call a getdoc() method on the given object.  This
     allows objects which provide their docstrings via non-standard mechanisms
     (like Pyro proxies) to still be inspected by ipython's ? system."""
 
     ds = None  # default return value
     try:
         ds = inspect.getdoc(obj)
     except:
         # Harden against an inspect failure, which can occur with
         # SWIG-wrapped extensions.
         pass
     # Allow objects to offer customized documentation via a getdoc method:
     try:
         ds2 = obj.getdoc()
     except:
         pass
     else:
         # if we get extra info, we add it to the normal docstring.
         if ds is None:
             ds = ds2
         else:
             ds = '%s\n%s' % (ds,ds2)
     return ds
 
+
 def getsource(obj,is_binary=False):
     """Wrapper around inspect.getsource.
 
     This can be modified by other projects to provide customized source
     extraction.
 
     Inputs:
 
     - obj: an object whose source code we will attempt to extract.
 
     Optional inputs:
 
     - is_binary: whether the object is known to come from a binary source.
     This implementation will skip returning any output for binary objects, but
     custom extractors may know how to meaningfully process them."""
     
     if is_binary:
         return None
     else:
         try:
             src = inspect.getsource(obj)
         except TypeError:
             if hasattr(obj,'__class__'):
                 src = inspect.getsource(obj.__class__)
         return src
 
+def getargspec(obj):
+    """Get the names and default values of a function's arguments.
+
+    A tuple of four things is returned: (args, varargs, varkw, defaults).
+    'args' is a list of the argument names (it may contain nested lists).
+    'varargs' and 'varkw' are the names of the * and ** arguments or None.
+    'defaults' is an n-tuple of the default values of the last n arguments.
+
+    Modified version of inspect.getargspec from the Python Standard
+    Library."""
+
+    if inspect.isfunction(obj):
+        func_obj = obj
+    elif inspect.ismethod(obj):
+        func_obj = obj.im_func
+    else:
+        raise TypeError, 'arg is not a Python function'
+    args, varargs, varkw = inspect.getargs(func_obj.func_code)
+    return args, varargs, varkw, func_obj.func_defaults
+
 #****************************************************************************
 # Class definitions
 
 class myStringIO(StringIO.StringIO):
     """Adds a writeln method to normal StringIO."""
     def writeln(self,*arg,**kw):
         """Does a write() and then a write('\n')"""
         self.write(*arg,**kw)
         self.write('\n')
 
+
 class Inspector:
     def __init__(self,color_table,code_color_table,scheme,
                  str_detail_level=0):
         self.color_table = color_table
         self.parser = PyColorize.Parser(code_color_table,out='str')
         self.format = self.parser.format
         self.str_detail_level = str_detail_level
         self.set_active_scheme(scheme)
 
-    def __getargspec(self,obj):
-        """Get the names and default values of a function's arguments.
-
-        A tuple of four things is returned: (args, varargs, varkw, defaults).
-        'args' is a list of the argument names (it may contain nested lists).
-        'varargs' and 'varkw' are the names of the * and ** arguments or None.
-        'defaults' is an n-tuple of the default values of the last n arguments.
-
-        Modified version of inspect.getargspec from the Python Standard
-        Library."""
-
-        if inspect.isfunction(obj):
-            func_obj = obj
-        elif inspect.ismethod(obj):
-            func_obj = obj.im_func
-        else:
-            raise TypeError, 'arg is not a Python function'
-        args, varargs, varkw = inspect.getargs(func_obj.func_code)
-        return args, varargs, varkw, func_obj.func_defaults
-
     def __getdef(self,obj,oname=''):
         """Return the definition header for any callable object.
 
         If any exception is generated, None is returned instead and the
         exception is suppressed."""
         
         try:
-            return oname + inspect.formatargspec(*self.__getargspec(obj))
+            return oname + inspect.formatargspec(*getargspec(obj))
         except:
             return None
  
     def __head(self,h):
         """Return a header string with proper colors."""
         return '%s%s%s' % (self.color_table.active_colors.header,h,
                            self.color_table.active_colors.normal)
 
     def set_active_scheme(self,scheme):
         self.color_table.set_active_scheme(scheme)
         self.parser.color_table.set_active_scheme(scheme)
     
     def noinfo(self,msg,oname):
         """Generic message when no information is found."""
         print 'No %s found' % msg,
         if oname:
             print 'for %s' % oname
         else:
             print
             
     def pdef(self,obj,oname=''):
         """Print the definition header for any callable object.
 
         If the object is a class, print the constructor information."""
 
         if not callable(obj):
             print 'Object is not callable.'
             return
 
         header = ''
 
         if inspect.isclass(obj):
             header = self.__head('Class constructor information:\n')
             obj = obj.__init__
         elif type(obj) is types.InstanceType:
             obj = obj.__call__
 
         output = self.__getdef(obj,oname)
         if output is None:
             self.noinfo('definition header',oname)
         else:
             print >>Term.cout, header,self.format(output),
 
     def pdoc(self,obj,oname='',formatter = None):
         """Print the docstring for any object.
 
         Optional:
         -formatter: a function to run the docstring through for specially
         formatted docstrings."""
 
         head = self.__head  # so that itpl can find it even if private
         ds = getdoc(obj)
         if formatter:
             ds = formatter(ds)
         if inspect.isclass(obj):
             init_ds = getdoc(obj.__init__)
             output = itpl('$head("Class Docstring:")\n'
                           '$indent(ds)\n'
                           '$head("Constructor Docstring"):\n'
                           '$indent(init_ds)')
         elif (type(obj) is types.InstanceType or isinstance(obj,object)) \
                  and hasattr(obj,'__call__'):
             call_ds = getdoc(obj.__call__)
             if call_ds:
                 output = itpl('$head("Class Docstring:")\n$indent(ds)\n'
                               '$head("Calling Docstring:")\n$indent(call_ds)')
             else:
                 output = ds
         else:
             output = ds
         if output is None:
             self.noinfo('documentation',oname)
             return
         page(output)
     
     def psource(self,obj,oname=''):
         """Print the source code for an object."""
 
         # Flush the source cache because inspect can return out-of-date source
         linecache.checkcache()
         try:
             src = getsource(obj) 
         except:
             self.noinfo('source',oname)
         else:
             page(self.format(src))
 
     def pfile(self,obj,oname=''):
         """Show the whole file where an object was defined."""
 
         try:
             try:
                 lineno = inspect.getsourcelines(obj)[1]
             except TypeError:
                 # For instances, try the class object like getsource() does
                 if hasattr(obj,'__class__'):
                     lineno = inspect.getsourcelines(obj.__class__)[1]
                     # Adjust the inspected object so getabsfile() below works
                     obj = obj.__class__
         except:
             self.noinfo('file',oname)
             return
 
         # We only reach this point if object was successfully queried
         
         # run contents of file through pager starting at line
         # where the object is defined
         ofile = inspect.getabsfile(obj)
 
         if (ofile.endswith('.so') or ofile.endswith('.dll')):
             print 'File %r is binary, not printing.' % ofile
         elif not os.path.isfile(ofile):
             print 'File %r does not exist, not printing.' % ofile
         else:
             # Print only text files, not extension binaries.  Note that
             # getsourcelines returns lineno with 1-offset and page() uses
             # 0-offset, so we must adjust.
             page(self.format(open(ofile).read()),lineno-1)
 
     def pinfo(self,obj,oname='',formatter=None,info=None,detail_level=0):
         """Show detailed information about an object.
 
         Optional arguments:
         
         - oname: name of the variable pointing to the object.
 
         - formatter: special formatter for docstrings (see pdoc)
 
         - info: a structure with some information fields which may have been
         precomputed already.
 
         - detail_level: if set to 1, more information is given.
         """
 
         obj_type = type(obj)
 
         header = self.__head
         if info is None:
             ismagic = 0
             isalias = 0
             ospace = ''
         else:
             ismagic = info.ismagic
             isalias = info.isalias
             ospace = info.namespace
         # Get docstring, special-casing aliases:
         if isalias:
             if not callable(obj):
                 try:
                     ds = "Alias to the system command:\n  %s" % obj[1]
                 except:
                     ds = "Alias: " + str(obj)
             else:
                 ds = "Alias to " + str(obj)
                 if obj.__doc__:
                     ds += "\nDocstring:\n" + obj.__doc__
         else:
             ds = getdoc(obj)
             if ds is None:
                 ds = '<no docstring>'
         if formatter is not None:
             ds = formatter(ds)
 
         # store output in a list which gets joined with \n at the end.
         out = myStringIO()
         
         string_max = 200 # max size of strings to show (snipped if longer)
         shalf = int((string_max -5)/2)
 
         if ismagic:
             obj_type_name = 'Magic function'
         elif isalias:
             obj_type_name = 'System alias'
         else:
             obj_type_name = obj_type.__name__
         out.writeln(header('Type:\t\t')+obj_type_name)
 
         try:
             bclass = obj.__class__
             out.writeln(header('Base Class:\t')+str(bclass))
         except: pass
 
         # String form, but snip if too long in ? form (full in ??)
         if detail_level >= self.str_detail_level:
             try:
                 ostr = str(obj)
                 str_head = 'String Form:'
                 if not detail_level and len(ostr)>string_max:
                     ostr = ostr[:shalf] + ' <...> ' + ostr[-shalf:]
                     ostr = ("\n" + " " * len(str_head.expandtabs())).\
                            join(map(string.strip,ostr.split("\n")))
                 if ostr.find('\n') > -1:
                     # Print multi-line strings starting at the next line.
                     str_sep = '\n'
                 else:
                     str_sep = '\t'
                 out.writeln("%s%s%s" % (header(str_head),str_sep,ostr))
             except:
                 pass
 
         if ospace:
             out.writeln(header('Namespace:\t')+ospace)
 
         # Length (for strings and lists)
         try:
             length = str(len(obj))
             out.writeln(header('Length:\t\t')+length)
         except: pass
 
         # Filename where object was defined
         binary_file = False
         try:
             try:
                 fname = inspect.getabsfile(obj)
             except TypeError:
                 # For an instance, the file that matters is where its class was
                 # declared.
                 if hasattr(obj,'__class__'):
                     fname = inspect.getabsfile(obj.__class__)
             if fname.endswith('<string>'):
                 fname = 'Dynamically generated function. No source code available.'
             if (fname.endswith('.so') or fname.endswith('.dll')):
                 binary_file = True
             out.writeln(header('File:\t\t')+fname)
         except:
             # if anything goes wrong, we don't want to show source, so it's as
             # if the file was binary
             binary_file = True
 
         # reconstruct the function definition and print it:
         defln = self.__getdef(obj,oname)
         if defln:
             out.write(header('Definition:\t')+self.format(defln))
  
         # Docstrings only in detail 0 mode, since source contains them (we
         # avoid repetitions).  If source fails, we add them back, see below.
         if ds and detail_level == 0:
                 out.writeln(header('Docstring:\n') + indent(ds))
                 
         # Original source code for any callable
         if detail_level:
             # Flush the source cache because inspect can return out-of-date
             # source
             linecache.checkcache()
             source_success = False
             try:
                 try:
                     src = getsource(obj,binary_file)
                 except TypeError:
                     if hasattr(obj,'__class__'):
                         src = getsource(obj.__class__,binary_file)
                 if src is not None:
                     source = self.format(src)
                     out.write(header('Source:\n')+source.rstrip())
                     source_success = True
             except Exception, msg:
                 pass
             
             if ds and not source_success:
                 out.writeln(header('Docstring [source file open failed]:\n')
                             + indent(ds))
 
         # Constructor docstring for classes
         if inspect.isclass(obj):
             # reconstruct the function definition and print it:
             try:
                 obj_init =  obj.__init__
             except AttributeError:
                 init_def = init_ds = None
             else:
                 init_def = self.__getdef(obj_init,oname)
                 init_ds  = getdoc(obj_init)
                 # Skip Python's auto-generated docstrings
                 if init_ds and \
                        init_ds.startswith('x.__init__(...) initializes'):
                     init_ds = None
 
             if init_def or init_ds:
                 out.writeln(header('\nConstructor information:'))
                 if init_def:
                     out.write(header('Definition:\t')+ self.format(init_def))
                 if init_ds:
                     out.writeln(header('Docstring:\n') + indent(init_ds))
         # and class docstring for instances:
         elif obj_type is types.InstanceType or \
                  isinstance(obj,object):
 
             # First, check whether the instance docstring is identical to the
             # class one, and print it separately if they don't coincide.  In
             # most cases they will, but it's nice to print all the info for
             # objects which use instance-customized docstrings.
             if ds:
                 try:
                     cls = getattr(obj,'__class__')
                 except:
                     class_ds = None
                 else:
                     class_ds = getdoc(cls)
                 # Skip Python's auto-generated docstrings
                 if class_ds and \
                        (class_ds.startswith('function(code, globals[,') or \
                    class_ds.startswith('instancemethod(function, instance,') or \
                    class_ds.startswith('module(name[,') ):
                     class_ds = None
                 if class_ds and ds != class_ds:
                     out.writeln(header('Class Docstring:\n') +
                                 indent(class_ds))
 
             # Next, try to show constructor docstrings
             try:
                 init_ds = getdoc(obj.__init__)
                 # Skip Python's auto-generated docstrings
                 if init_ds and \
                        init_ds.startswith('x.__init__(...) initializes'):
                     init_ds = None
             except AttributeError:
                 init_ds = None
             if init_ds:
                 out.writeln(header('Constructor Docstring:\n') +
                             indent(init_ds))
 
             # Call form docstring for callable instances
             if hasattr(obj,'__call__'):
                 #out.writeln(header('Callable:\t')+'Yes')
                 call_def = self.__getdef(obj.__call__,oname)
                 #if call_def is None:
                 #    out.writeln(header('Call def:\t')+
                 #              'Calling definition not available.')
                 if call_def is not None:
                     out.writeln(header('Call def:\t')+self.format(call_def))
                 call_ds = getdoc(obj.__call__)
                 # Skip Python's auto-generated docstrings
                 if call_ds and call_ds.startswith('x.__call__(...) <==> x(...)'):
                     call_ds = None
                 if call_ds:
                     out.writeln(header('Call docstring:\n') + indent(call_ds))
 
         # Finally send to printer/pager
         output = out.getvalue()
         if output:
             page(output)
         # end pinfo
 
     def psearch(self,pattern,ns_table,ns_search=[],
                 ignore_case=False,show_all=False):
         """Search namespaces with wildcards for objects.
 
         Arguments:
 
         - pattern: string containing shell-like wildcards to use in namespace
         searches and optionally a type specification to narrow the search to
         objects of that type.
 
         - ns_table: dict of name->namespaces for search.
 
         Optional arguments:
         
           - ns_search: list of namespace names to include in search.
 
           - ignore_case(False): make the search case-insensitive.
 
           - show_all(False): show all names, including those starting with
           underscores.
         """
         #print 'ps pattern:<%r>' % pattern # dbg
         
         # defaults
         type_pattern = 'all'
         filter = ''
 
         cmds = pattern.split()
         len_cmds  =  len(cmds)
         if len_cmds == 1:
             # Only filter pattern given
             filter = cmds[0]
         elif len_cmds == 2:
             # Both filter and type specified
             filter,type_pattern = cmds
         else:
             raise ValueError('invalid argument string for psearch: <%s>' %
                              pattern)
 
         # filter search namespaces
         for name in ns_search:
             if name not in ns_table:
                 raise ValueError('invalid namespace <%s>. Valid names: %s' %
                                  (name,ns_table.keys()))
 
         #print 'type_pattern:',type_pattern # dbg
         search_result = []
         for ns_name in ns_search:
             ns = ns_table[ns_name]
             tmp_res = list(list_namespace(ns,type_pattern,filter,
                                           ignore_case=ignore_case,
                                           show_all=show_all))
             search_result.extend(tmp_res)
         search_result.sort()
 
         page('\n'.join(search_result))