| msg28277 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-04-18 12:16 |
| Pdb 'run/runeval' commands fails to check the type of given argument.When argument to 'run/runeval' is non-string the functions crashes with further impilications on (correctly)invoking this functions: Python 2.5a1 (trunk:45527, Apr 18 2006, 11:12:31) >>> def x(): pass >>> import pdb >>> pdb.run(x()) Traceback (most recent call last): File "", line 1, in File "/home/jkk/python/python-svn/Lib/pdb.py", line 1113, in run Pdb().run(statement, globals, locals) File "/home/jkk/python/python-svn/Lib/bdb.py", line 363, in run cmd = cmd+'\n' TypeError: unsupported operand type(s) for +: 'NoneType' and 'str' >>> pdb.run('x()') > /home/jkk/python/python-svn/Lib/pdb.py(1113)run() -> Pdb().run(statement, globals, locals) (Pdb) # CTRL-D pressed Traceback (most recent call last): File "", line 1, in File "/home/jkk/python/python-svn/Lib/pdb.py", line 1113, in run Pdb().run(statement, globals, locals) File "/home/jkk/python/python-svn/Lib/pdb.py", line 1113, in run Pdb().run(statement, globals, locals) File "/home/jkk/python/python-svn/Lib/bdb.py", line 48, in trace_dispatch return self.dispatch_line(frame) File "/home/jkk/python/python-svn/Lib/bdb.py", line 67, in dispatch_line if self.quitting: raise BdbQuit bdb.BdbQuit The solution is to simply ensure that the first argument passed to the 'run/runeval' functions is string. |
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| msg28278 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-04-18 12:36 |
| Logged In: YES user_id=1491175 Patch is in #1472257 |
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| msg28279 - (view) |
Author: Ilya Sandler (isandler) |
Date: 2006-05-21 23:25 |
| Logged In: YES user_id=971153 I would not classify your example as a crash. You passed a wrong value (None in your case) into pdb.run() and got back a TypeError...Isn't it an expected response? E.g if you do: >>>max(13) You'll also get: "TypeError" Am I missing something? Could you clarify? |
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| msg28280 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-05-22 09:20 |
| Logged In: YES user_id=1491175 The point is that when you want to invoke pdb.run correctly (with string argument) after getting TypeError as in above example, your namespace is probably overwritten or deleted so that you don't have access to previously defined symbols. >>> def x():pass >>> import pdb >>> pdb.run(x()) TypeError >>> pdb.run('x()') > /home/jkk/python-svn/Lib/pdb.py(1122)run() -> Pdb().run(statement, globals, locals) (Pdb) pdb *** NameError: name 'pdb' is not defined (Pdb) x *** NameError: name 'x' is not defined |
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| msg28281 - (view) |
Author: Ilya Sandler (isandler) |
Date: 2006-05-23 03:36 |
| Logged In: YES user_id=971153 Well, I don't see anything in bdb's run which could overwrite your namespace.. What seems to be happenning in your example is that bdb's first line event happens while bdb is still in run(), so you when you see pdb's prompt, are in bdb's namespace not in yours.. If you do "next" you will get where you should be.. bagira:~> python2.4 Python 2.4.1 (#2, May 5 2005, 11:32:06) >>> def x(): print "in x" >>> import pdb >>> pdb.run( x()) in x TypeError: unsupported operand type(s) for +: 'NoneType' and 'str' >>> pdb.run( 'x()' ) > /usr/lib/python2.4/pdb.py(987)run() -> Pdb().run(statement, globals, locals) (Pdb) n #now you are back in your namespace > (1)?() (Pdb) p x #and you get your symbols back <function x at 0x4021be2c> (Pdb) p pdb <module 'pdb' from '/usr/lib/python2.4/pdb.pyc'> (Pdb) n in x --Return-- > (1)?()->None What do you think? |
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| msg28282 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-06-19 13:48 |
| Logged In: YES user_id=1491175 You're right,but don't you think that this kind of switching between namespaces could confuse users? |
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| msg28283 - (view) |
Author: Ilya Sandler (isandler) |
Date: 2006-06-25 18:54 |
| Logged In: YES user_id=971153 I have looked at what's happening in a bit more detail and now I agree that the current behaviour seems wrong. Apparently, when one passes a nonstring to bdb's run(), bdb sets tracing first and only then throws an exception... Leaving tracing on seems like a bad thing to do Would calling settrace() a couple lines later be the simplest solution then? so relevant fragment of bdb.py's run() becomes: if not isinstance(cmd, types.CodeType): cmd = cmd+'\n' sys.settrace(self.trace_dispatch) This should prevent bdb from turning tracing too early. What do you think? |
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| msg28284 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-07-11 14:02 |
| Logged In: YES user_id=1491175 Is your comment directly related to this bug? Maybe you should create separete bug tracker item to discuss problem presented in your comment? |
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| msg28285 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-07-11 15:02 |
| Logged In: YES user_id=1491175 Simple solution is to catch TypeError in bdb's run function: try: if not isinstance(cmd, types.CodeType): cmd = cmd+'\n' except TypeError: pass Now it seems that handling nonstring arguments is better: >>> import pdb >>> def x():pass ... >>> pdb.run(x()) Traceback (most recent call last): File "", line 1, in File "/home/jkk/python-svn/Lib/pdb.py", line 1122, in run Pdb().run(statement, globals, locals) File "/home/jkk/python-svn/Lib/bdb.py", line 369, in run exec cmd in globals, locals TypeError: exec: arg 1 must be a string, file, or code object >>> pdb.run('x()') > (1)() (Pdb) x <function x at 0x4024a9cc> (Pdb) pdb.run('x()') (Pdb) >>> |
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| msg28286 - (view) |
Author: Ilya Sandler (isandler) |
Date: 2006-07-22 17:46 |
| Logged In: YES user_id=971153 >> Is your comment directly related to this bug? Yes, my suggestion was to call settrace() after cmd = cmd+'\n' which should solve the original (bdb leaving tracing on) problem.. Your latest suggestion would do the same thing by different means.. However, I think there an even better way: can we simply remove - if not isinstance(cmd, types.CodeType): - cmd = cmd+'\n' from bdb.py??? This would both solve the original problem and make error message more meaningful IMO.. > exec: arg 1 must be a string, file, or code object Rather than: >Unsupported operand type(s) for +: 'NoneType' and 'str' This seems to work for me, would you be interested in testing and submitting a patch for this? A bit more information: it appears that older versions of python in some cases required string passed to exec to end with '\n', this was even mentioned in python FAQ.. E.g if I feed exec 'for i in range(4):\nx=i' into python2.1, I get a Syntax error.. However, this does work in python2.3.3, 2.4,2.5... So was this + '\n' indeed a workaround for a deficiency in exec? apparently older versions of python required the string passed to exec to end with '\n'. It was even mentioned in older FAQs... However, latest versions of python seem to accept strings without new line... Eg. even |
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| msg28287 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2006-07-26 11:25 |
| Logged In: YES user_id=1491175 I think your solution works for me too;)I attached patch which modify run and runeval function according to your suggestion. I tested both run and runeval functions with string and code object as an argument,and also run with file object. It appears that patch works fine. |
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| msg83909 - (view) |
Author: Daniel Diniz (ajaksu2) *  |
Date: 2009-03-21 02:13 |
| Issue 1472257 was rejected. |
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| msg93041 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2009-09-23 14:43 |
| Updated patch with tests and documentation.It fixes the issue by leaving argument checking to exec and eval functions.The result is a more readable error messages when invoking run/runeval with incorrect arguments (see discussion above) and also ability to run pdb on an open file objects. |
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| msg93042 - (view) |
Author: Kuba Kończyk (jakamkon) |
Date: 2009-09-23 15:07 |
| BTW, patch is based on trunk. |
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| msg112052 - (view) |
Author: Georg Brandl (georg.brandl) *  |
Date: 2010-07-30 09:14 |
| Committed in trunk r83266; file objects are no longer allowed for exec(), therefore I dropped mentions of that. |
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