Oinspect.py: Only show docstring for nonexisting/binary files

when doing object??, closing ticket  #62

IPython/OInspect.py

@@ -1,475 +1,483 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 1058 2006-01-22 14:30:01Z vivainio $
+$Id: OInspect.py 1300 2006-05-15 16:27:36Z vivainio $
 """
 
 #*****************************************************************************
 #       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 inspect
 import linecache
 import string
 import StringIO
 import types
-
+import os
 # IPython's own
 from IPython import PyColorize
 from IPython.genutils import page,indent,Term,mkdict
 from IPython.Itpl import itpl
 from IPython.wildcard import list_namespace
 from IPython.ColorANSI import *
 
 #****************************************************************************
 # 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
 
 #****************************************************************************
 # 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):
         self.color_table = color_table
         self.parser = PyColorize.Parser(code_color_table,out='str')
         self.format = self.parser.format
         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))
         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 type(obj) is types.ClassType:
             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 type(obj) is types.ClassType:
             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 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 = inspect.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:
             sourcelines,lineno = inspect.getsourcelines(obj)
         except:
             self.noinfo('file',oname)
         else:
             # 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.
                 page(self.format(open(ofile).read()),lineno)
             #page(self.format(open(inspect.getabsfile(obj)).read()),lineno)
 
     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:
             ds = "Alias to the system command:\n  %s" % obj[1]
         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 ??)
         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:
             fname = inspect.getabsfile(obj)
             if fname.endswith('<string>'):
                 fname = 'Dynamically generated function. No source code available.'
-            if fname.endswith('.so') or fname.endswith('.dll'):
+            if (fname.endswith('.so') or fname.endswith('.dll') or 
+                not os.path.isfile(fname)):
                 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:
                 if not binary_file:
                     source = self.format(inspect.getsource(obj))
                     out.write(header('Source:\n')+source.rstrip())
+                    source_success = True
             except:
-                if ds:
-                    out.writeln(header('Docstring:\n') + indent(ds))
+                pass
+            
+            if ds and not source_success:
+                out.writeln(header('Docstring [source file open failed]:\n') + indent(ds))
 
         # Constructor docstring for classes
         if obj_type is types.ClassType:
             # 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)
 
             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:
 
             # 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:
                 class_ds = getdoc(obj.__class__)
                 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__)
             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.write(header('Call def:\t')+
                               'Calling definition not available.')
                 else:
                     out.write(header('Call def:\t')+self.format(call_def))
                 call_ds = getdoc(obj.__call__)
                 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.
         """
         # 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))