Merged revisions 83259,83261,83264-83265,83268-83269,83271-83272,83281 via svnmerge from
svn+ssh://svn.python.org/python/branches/py3k

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  r83259 | georg.brandl | 2010-07-30 09:03:39 +0200 (Fr, 30 Jul 2010) | 1 line

  Clarification.
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  r83261 | georg.brandl | 2010-07-30 09:21:26 +0200 (Fr, 30 Jul 2010) | 1 line

  #9230: allow Pdb.checkline() to be called without a current frame, for setting breakpoints before starting debugging.
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  r83264 | georg.brandl | 2010-07-30 10:45:26 +0200 (Fr, 30 Jul 2010) | 1 line

  Document the "jump" command in pdb.__doc__, and add a version tag for "until X".
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  r83265 | georg.brandl | 2010-07-30 10:54:49 +0200 (Fr, 30 Jul 2010) | 1 line

  #8015: fix crash when entering an empty line for breakpoint commands.  Also restore environment properly when an exception occurs during the definition of commands.
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  r83268 | georg.brandl | 2010-07-30 11:23:23 +0200 (Fr, 30 Jul 2010) | 2 lines

  Issue #8048: Prevent doctests from failing when sys.displayhook has
  been reassigned.
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  r83269 | georg.brandl | 2010-07-30 11:43:00 +0200 (Fr, 30 Jul 2010) | 1 line

  #6719: In pdb, do not stop somewhere in the encodings machinery if the source file to be debugged is in a non-builtin encoding.
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  r83271 | georg.brandl | 2010-07-30 11:59:28 +0200 (Fr, 30 Jul 2010) | 1 line

  #5727: Restore the ability to use readline when calling into pdb in doctests.
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  r83272 | georg.brandl | 2010-07-30 12:29:19 +0200 (Fr, 30 Jul 2010) | 1 line

  #5294: Fix the behavior of pdb "continue" command when called in the top-level debugged frame.
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  r83281 | georg.brandl | 2010-07-30 15:36:43 +0200 (Fr, 30 Jul 2010) | 1 line

  Add myself for pdb.
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diff --git a/Lib/pdb.py b/Lib/pdb.py
index 22dcff7..1fb5174 100755
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@@ -183,6 +183,8 @@
 
     def user_return(self, frame, return_value):
         """This function is called when a return trap is set here."""
+        if self._wait_for_mainpyfile:
+            return
         frame.f_locals['__return__'] = return_value
         print('--Return--', file=self.stdout)
         self.interaction(frame, None)
@@ -190,6 +192,8 @@
     def user_exception(self, frame, exc_info):
         """This function is called if an exception occurs,
         but only if we are to stop at or just below this level."""
+        if self._wait_for_mainpyfile:
+            return
         exc_type, exc_value, exc_traceback = exc_info
         frame.f_locals['__exception__'] = exc_type, exc_value
         exc_type_name = exc_type.__name__
@@ -275,8 +279,10 @@
             return self.handle_command_def(line)
 
     def handle_command_def(self,line):
-        """ Handles one command line during command list definition. """
+        """Handles one command line during command list definition."""
         cmd, arg, line = self.parseline(line)
+        if not cmd:
+            return
         if cmd == 'silent':
             self.commands_silent[self.commands_bnum] = True
             return # continue to handle other cmd def in the cmd list
@@ -284,7 +290,7 @@
             self.cmdqueue = []
             return 1 # end of cmd list
         cmdlist = self.commands[self.commands_bnum]
-        if (arg):
+        if arg:
             cmdlist.append(cmd+' '+arg)
         else:
             cmdlist.append(cmd)
@@ -327,9 +333,11 @@
         prompt_back = self.prompt
         self.prompt = '(com) '
         self.commands_defining = True
-        self.cmdloop()
-        self.commands_defining = False
-        self.prompt = prompt_back
+        try:
+            self.cmdloop()
+        finally:
+            self.commands_defining = False
+            self.prompt = prompt_back
 
     def do_break(self, arg, temporary = 0):
         # break [ ([filename:]lineno | function) [, "condition"] ]
@@ -465,7 +473,10 @@
         Return `lineno` if it is, 0 if not (e.g. a docstring, comment, blank
         line or EOF). Warning: testing is not comprehensive.
         """
-        line = linecache.getline(filename, lineno, self.curframe.f_globals)
+        # this method should be callable before starting debugging, so default
+        # to "no globals" if there is no current frame
+        globs = self.curframe.f_globals if hasattr(self, 'curframe') else None
+        line = linecache.getline(filename, lineno, globs)
         if not line:
             print('End of file', file=self.stdout)
             return 0
@@ -1293,7 +1304,7 @@
     # changed by the user from the command line. There is a "restart" command
     # which allows explicit specification of command line arguments.
     pdb = Pdb()
-    while 1:
+    while True:
         try:
             pdb._runscript(mainpyfile)
             if pdb._user_requested_quit: