pdb support in threaded mode, replaced the crash handler with a verbose

traceback printer for threaded shells.

IPython/Magic.py

@@ -1,7 +1,7 b''
 # -*- coding: utf-8 -*-
 """Magic functions for InteractiveShell.
 
-$Id: Magic.py 962 2005-12-28 18:04:59Z fperez $"""
+$Id: Magic.py 965 2005-12-28 23:23:09Z fperez $"""
 
 #*****************************************************************************
 #       Copyright (C) 2001 Janko Hauser <[e-mail]> and
@@ -1049,14 +1049,21 b' Currently the magic system has the following functions:\\n"""'
             try:
                 pdb = {'off':0,'0':0,'on':1,'1':1}[par]
             except KeyError:
-                print 'Incorrect argument. Use on/1, off/0 or nothing for a toggle.'
+                print 'Incorrect argument. Use on/1, off/0, or nothing for a toggle.'
                 return
             else:
                self.shell.InteractiveTB.call_pdb = pdb 
         else:
-            self.shell.InteractiveTB.call_pdb = 1 - self.shell.InteractiveTB.call_pdb
-        print 'Automatic pdb calling has been turned',\
-              on_off(self.shell.InteractiveTB.call_pdb)
+            new_pdb = not self.shell.InteractiveTB.call_pdb
+            self.shell.InteractiveTB.call_pdb = new_pdb
+            if self.shell.isthreaded:
+                try:
+                    self.sys_excepthook.call_pdb = new_pdb
+                except:
+                    warn('Failed to activate pdb for threaded exception handler')
+                
+        print 'Automatic pdb calling has been turned',on_off(new_pdb)
+
 
 
     def magic_prun(self, parameter_s ='',user_mode=1,
@@ -1895,12 +1902,23 b' Currently the magic system has the following functions:\\n"""'
 
         If called without arguments, acts as a toggle."""
 
+        def xmode_switch_err(name):
+            warn('Error changing %s exception modes.\n%s' %
+                 (name,sys.exc_info()[1]))
+
         new_mode = parameter_s.strip().capitalize()
         try:
-            self.InteractiveTB.set_mode(mode = new_mode)
+            self.InteractiveTB.set_mode(mode=new_mode)
             print 'Exception reporting mode:',self.InteractiveTB.mode
         except:
-            warn('Error changing exception modes.\n' + str(sys.exc_info()[1]))
+            xmode_switch_err('user')
+
+        # threaded shells use a special handler in sys.excepthook
+        if self.isthreaded:
+            try:
+                self.shell.sys_excepthook.set_mode(mode=new_mode)
+            except:
+                xmode_switch_err('threaded')
             
     def magic_colors(self,parameter_s = ''):
         """Switch color scheme for prompts, info system and exception handlers.
@@ -1908,6 +1926,11 b' Currently the magic system has the following functions:\\n"""'
         Currently implemented schemes: NoColor, Linux, LightBG.
 
         Color scheme names are not case-sensitive."""
+
+        def color_switch_err(name):
+            warn('Error changing %s color schemes.\n%s' %
+                 (name,sys.exc_info()[1]))
+            
         
         new_scheme = parameter_s.strip()
         if not new_scheme:
@@ -1943,8 +1966,7 b' Defaulting color scheme to \'NoColor\'"""'
         try:
             self.shell.outputcache.set_colors(new_scheme)
         except:
-            warn('Error changing prompt color schemes.\n'
-                 + str(sys.exc_info()[1]))
+            color_switch_err('prompt')
         else:
             self.shell.rc.colors = \
                        self.shell.outputcache.color_table.active_scheme_name
@@ -1953,15 +1975,21 b' Defaulting color scheme to \'NoColor\'"""'
             self.shell.InteractiveTB.set_colors(scheme = new_scheme)
             self.shell.SyntaxTB.set_colors(scheme = new_scheme)
         except:
-            warn('Error changing exception color schemes.\n'
-                 + str(sys.exc_info()[1]))
+            color_switch_err('exception')
+
+        # threaded shells use a verbose traceback in sys.excepthook
+        if self.isthreaded:
+            try:
+                self.shell.sys_excepthook.set_colors(scheme=new_scheme)
+            except:
+                color_switch_err('system exception handler')
+        
         # Set info (for 'object?') colors
         if self.shell.rc.color_info:
             try:
                 self.shell.inspector.set_active_scheme(new_scheme)
             except:
-                warn('Error changing object inspector color schemes.\n'
-                     + str(sys.exc_info()[1]))
+                color_switch_err('object inspector')
         else:
             self.shell.inspector.set_active_scheme('NoColor')
                 

IPython/Shell.py

@@ -4,7 +4,7 b''
 All the matplotlib support code was co-developed with John Hunter,
 matplotlib's author.
 
-$Id: Shell.py 964 2005-12-28 21:03:01Z fperez $"""
+$Id: Shell.py 965 2005-12-28 23:23:09Z fperez $"""
 
 #*****************************************************************************
 #       Copyright (C) 2001-2004 Fernando Perez <[e-mail]>
@@ -260,6 +260,10 b' class MTInteractiveShell(InteractiveShell):'
     # McErlean and John Finlay.  Modified with corrections by Antoon Pardon,
     # from the pygtk mailing list, to avoid lockups with system calls.
 
+    # class attribute to indicate whether the class supports threads or not.
+    # Subclasses with thread support should override this as needed.
+    isthreaded = True
+
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns=None,user_global_ns=None,banner2='',**kw):
         """Similar to the normal InteractiveShell, but with threading control"""

IPython/iplib.py

@@ -6,7 +6,7 b' Requires Python 2.1 or newer.'
 
 This file contains all the classes and helper functions specific to IPython.
 
-$Id: iplib.py 964 2005-12-28 21:03:01Z fperez $
+$Id: iplib.py 965 2005-12-28 23:23:09Z fperez $
 """
 
 #*****************************************************************************
@@ -232,6 +232,10 b' class SyntaxTB(ultraTB.ListTB):'
 class InteractiveShell(Logger, Magic):
     """An enhanced console for Python."""
 
+    # class attribute to indicate whether the class supports threads or not.
+    # Subclasses with thread support should override this as needed.
+    isthreaded = False
+
     def __init__(self,name,usage=None,rc=Struct(opts=None,args=None),
                  user_ns = None,user_global_ns=None,banner2='',
                  custom_exceptions=((),None),embedded=False):
@@ -268,6 +272,9 b' class InteractiveShell(Logger, Magic):'
         except AttributeError:
             pass
 
+        # Store the actual shell's name
+        self.name = name
+
         # We need to know whether the instance is meant for embedding, since
         # global/local namespaces need to be handled differently in that case
         self.embedded = embedded
@@ -405,9 +412,6 b' class InteractiveShell(Logger, Magic):'
         self.user_ns['In']  = self.input_hist
         self.user_ns['Out'] = self.output_hist
 
-        # Store the actual shell's name
-        self.name = name
-
         # Object variable to store code object waiting execution.  This is
         # used mainly by the multithreaded shells, but it can come in handy in
         # other situations.  No need to use a Queue here, since it's a single
@@ -565,14 +569,35 b' class InteractiveShell(Logger, Magic):'
         self.banner2 = banner2
 
         # TraceBack handlers:
-        # Need two, one for syntax errors and one for other exceptions.
+
+        # Syntax error handler.
         self.SyntaxTB = SyntaxTB(color_scheme='NoColor')
+        
         # The interactive one is initialized with an offset, meaning we always
         # want to remove the topmost item in the traceback, which is our own
         # internal code. Valid modes: ['Plain','Context','Verbose']
         self.InteractiveTB = ultraTB.AutoFormattedTB(mode = 'Plain',
                                                      color_scheme='NoColor',
                                                      tb_offset = 1)
+
+        # IPython itself shouldn't crash. This will produce a detailed
+        # post-mortem if it does.  But we only install the crash handler for
+        # non-threaded shells, the threaded ones use a normal verbose reporter
+        # and lose the crash handler.  This is because exceptions in the main
+        # thread (such as in GUI code) propagate directly to sys.excepthook,
+        # and there's no point in printing crash dumps for every user exception.
+        if self.isthreaded:
+            sys.excepthook = ultraTB.FormattedTB()
+        else:
+            from IPython import CrashHandler
+            sys.excepthook = CrashHandler.CrashHandler(self)
+
+        # The instance will store a pointer to this, so that runtime code
+        # (such as magics) can access it.  This is because during the
+        # read-eval loop, it gets temporarily overwritten (to deal with GUI
+        # frameworks).
+        self.sys_excepthook = sys.excepthook
+
         # and add any custom exception handlers the user may have specified
         self.set_custom_exc(*custom_exceptions)
 
@@ -618,6 +643,38 b' class InteractiveShell(Logger, Magic):'
         self.init_auto_alias()
     # end __init__
 
+    def post_config_initialization(self):
+        """Post configuration init method
+
+        This is called after the configuration files have been processed to
+        'finalize' the initialization."""
+
+        rc = self.rc
+        
+        # Load readline proper
+        if rc.readline:
+            self.init_readline()
+
+        # Set user colors (don't do it in the constructor above so that it
+        # doesn't crash if colors option is invalid)
+        self.magic_colors(rc.colors)
+
+        # Load user aliases
+        for alias in rc.alias:
+            self.magic_alias(alias)
+
+        # dynamic data that survives through sessions
+        # XXX make the filename a config option?
+        persist_base = 'persist'
+        if rc.profile:
+            persist_base += '_%s' % rc.profile
+        self.persist_fname =  os.path.join(rc.ipythondir,persist_base)
+
+        try:
+            self.persist = pickle.load(file(self.persist_fname))
+        except:
+            self.persist = {}
+            
     def set_hook(self,name,hook):
         """set_hook(name,hook) -> sets an internal IPython hook.
 
@@ -727,38 +784,6 b' class InteractiveShell(Logger, Magic):'
             self.Completer.namespace = self.user_ns
             self.Completer.global_namespace = self.user_global_ns
 
-    def post_config_initialization(self):
-        """Post configuration init method
-
-        This is called after the configuration files have been processed to
-        'finalize' the initialization."""
-
-        rc = self.rc
-        
-        # Load readline proper
-        if rc.readline:
-            self.init_readline()
-
-        # Set user colors (don't do it in the constructor above so that it
-        # doesn't crash if colors option is invalid)
-        self.magic_colors(rc.colors)
-
-        # Load user aliases
-        for alias in rc.alias:
-            self.magic_alias(alias)
-
-        # dynamic data that survives through sessions
-        # XXX make the filename a config option?
-        persist_base = 'persist'
-        if rc.profile:
-            persist_base += '_%s' % rc.profile
-        self.persist_fname =  os.path.join(rc.ipythondir,persist_base)
-
-        try:
-            self.persist = pickle.load(file(self.persist_fname))
-        except:
-            self.persist = {}
-            
     def init_auto_alias(self):
         """Define some aliases automatically.
 
@@ -1462,6 +1487,10 b' want to merge them back into the new files.""" % locals()'
         # Set our own excepthook in case the user code tries to call it
         # directly, so that the IPython crash handler doesn't get triggered
         old_excepthook,sys.excepthook = sys.excepthook, self.excepthook
+
+        # we save the original sys.excepthook in the instance, in case config
+        # code (such as magics) needs access to it.
+        self.sys_excepthook = old_excepthook
         outflag = 1  # happens in more places, so it's easier as default
         try:
             try:
@@ -1954,7 +1983,7 b' want to merge them back into the new files.""" % locals()'
             try:
                 execfile(fname,*where)
             except SyntaxError:
-                etype, evalue = sys.exc_info()[0:2]
+                etype,evalue = sys.exc_info()[:2]
                 self.SyntaxTB(etype,evalue,[])
                 warn('Failure executing file: <%s>' % fname)
             except SystemExit,status:

IPython/ipmaker.py

@@ -6,7 +6,7 b' Requires Python 2.1 or better.'
 
 This file contains the main make_IPython() starter function.
 
-$Id: ipmaker.py 964 2005-12-28 21:03:01Z fperez $"""
+$Id: ipmaker.py 965 2005-12-28 23:23:09Z fperez $"""
 
 #*****************************************************************************
 #       Copyright (C) 2001-2004 Fernando Perez. <[e-mail]>
@@ -94,15 +94,11 b' def make_IPython(argv=None,user_ns=None,user_global_ns=None,debug=1,'
     from site import _Helper
     IP.user_ns['help'] = _Helper()
 
+
     if DEVDEBUG:
         # For developer debugging only (global flag)
         from IPython import ultraTB
         sys.excepthook = ultraTB.VerboseTB(call_pdb=1)
-    else:
-        # IPython itself shouldn't crash. This will produce a detailed
-        # post-mortem if it does
-        from IPython import CrashHandler
-        sys.excepthook = CrashHandler.CrashHandler(IP)
 
     IP.BANNER_PARTS = ['Python %s\n'
                          'Type "copyright", "credits" or "license" '

IPython/ultraTB.py

@@ -60,7 +60,7 b' You can implement other color schemes easily, the syntax is fairly'
 self-explanatory. Please send back new schemes you develop to the author for
 possible inclusion in future releases.
 
-$Id: ultraTB.py 958 2005-12-27 23:17:51Z fperez $"""
+$Id: ultraTB.py 965 2005-12-28 23:23:09Z fperez $"""
 
 #*****************************************************************************
 #       Copyright (C) 2001 Nathaniel Gray <[e-mail]>
@@ -621,10 +621,10 b' class VerboseTB(TBTools):'
     # out the right info on its own.
     def __call__(self, etype=None, evalue=None, etb=None):
         """This hook can replace sys.excepthook (for Python 2.1 or higher)."""
-        if etb is not None:
-            self.handler((etype, evalue, etb))
-        else:
+        if etb is None:
             self.handler()
+        else:
+            self.handler((etype, evalue, etb))
         self.debugger()
 
 #----------------------------------------------------------------------------

doc/ChangeLog

@@ -5,8 +5,20 b''
 	questions part 2 - \/ characters revisited' on the iypthon user
 	list:
 	http://scipy.net/pipermail/ipython-user/2005-June/000907.html
+
 	(InteractiveShell.__init__): fix tab-completion bug in threaded shells.
 
+	(InteractiveShell.__init__): change threaded shells to not use the
+	ipython crash handler.  This was causing more problems than not,
+	as exceptions in the main thread (GUI code, typically) would
+	always show up as a 'crash', when they really weren't.
+
+	The colors and exception mode commands (%colors/%xmode) have been
+	synchronized to also take this into account, so users can get
+	verbose exceptions for their threaded code as well.  I also added
+	support for activating pdb inside this exception handler as well,
+	so now GUI authors can use IPython's enhanced pdb at runtime.
+
 	* IPython/ipmaker.py (make_IPython): make the autoedit_syntax flag
 	true by default, and add it to the shipped ipythonrc file.  Since
 	this asks the user before proceeding, I think it's OK to make it