ipython2/ipython3 prompt crashed when input 「n = collections.namedtuple?」(under Ubuntu_16)

[ming2281]

Description

Actual

When I input n = collections.namedtuple?, the ipython crashed

Except

The ipython works fine

Reproduce

1. you must have an ubuntu server 16 x64
2. input ipython3
3. input import collections
4. input n = collections.namedtuple?
5. then the IPython crashed and exited
6. input ipython2
7. do the same thing as above, then the ipython2 crashed and exited

Code

• My crash code

ipython3
Python 3.5.2 (default, Nov 17 2016, 17:05:23) 
Type "copyright", "credits" or "license" for more information.

IPython 5.2.2 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

In [1]: import collections

In [2]: n = collections.namedtuple?
Signature: collections.namedtuple(typename, field_names, verbose=False, rename=False)
Docstring:
Returns a new subclass of tuple with named fields.

>>> Point = namedtuple('Point', ['x', 'y'])
>>> Point.__doc__                   # docstring for the new class
'Point(x, y)'
>>> p = Point(11, y=22)             # instantiate with positional args or keywords
>>> p[0] + p[1]                     # indexable like a plain tuple
33
>>> x, y = p                        # unpack like a regular tuple
>>> x, y
(11, 22)
>>> p.x + p.y                       # fields also accessible by name
33
>>> d = p._asdict()                 # convert to a dictionary
>>> d['x']
11
>>> Point(**d)                      # convert from a dictionary
Point(x=11, y=22)
>>> p._replace(x=100)               # _replace() is like str.replace() but targets named fields
Point(x=100, y=22)
File:      /usr/lib/python3.5/collections/__init__.py
Type:      function

In [3]: n = collections.namedtuple?                                                                                                                                                            
Traceback (most recent call last):
  File "/usr/local/bin/ipython3", line 11, in <module>
    sys.exit(start_ipython())
  File "/usr/local/lib/python3.5/dist-packages/IPython/__init__.py", line 119, in start_ipython
    return launch_new_instance(argv=argv, **kwargs)
  File "/usr/local/lib/python3.5/dist-packages/traitlets/config/application.py", line 658, in launch_instance
    app.start()
  File "/usr/local/lib/python3.5/dist-packages/IPython/terminal/ipapp.py", line 348, in start
    self.shell.mainloop()
  File "/usr/local/lib/python3.5/dist-packages/IPython/terminal/interactiveshell.py", line 455, in mainloop
    self.interact()
  File "/usr/local/lib/python3.5/dist-packages/IPython/terminal/interactiveshell.py", line 438, in interact
    code = self.prompt_for_code()
  File "/usr/local/lib/python3.5/dist-packages/IPython/terminal/interactiveshell.py", line 343, in prompt_for_code
    pre_run=self.pre_prompt, reset_current_buffer=True)
  File "/usr/local/lib/python3.5/dist-packages/prompt_toolkit/interface.py", line 408, in run
    self._pre_run(pre_run)
  File "/usr/local/lib/python3.5/dist-packages/prompt_toolkit/interface.py", line 383, in _pre_run
    pre_run()
  File "/usr/local/lib/python3.5/dist-packages/IPython/terminal/interactiveshell.py", line 425, in pre_prompt
    self.pt_cli.application.buffer.text = cast_unicode_py2(self.rl_next_input)
  File "/usr/local/lib/python3.5/dist-packages/prompt_toolkit/buffer.py", line 371, in text
    assert self.cursor_position <= len(value)
AssertionError

If you suspect this is an IPython bug, please report it at:
    https://github.com/ipython/ipython/issues
or send an email to the mailing list at ipython-dev@scipy.org

You can print a more detailed traceback right now with "%tb", or use "%debug"
to interactively debug it.

Extra-detailed tracebacks for bug-reporting purposes can be enabled via:
    %config Application.verbose_crash=True

Environment

• Ubuntu Server

Linux VM-54-125-ubuntu 4.4.0-53-generic #74-Ubuntu SMP Fri Dec 2 15:59:10 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

• IPython

{'commit_hash': u'5be56c7',
 'commit_source': 'installation',
 'default_encoding': 'ANSI_X3.4-1968',
 'ipython_path': '/usr/local/lib/python2.7/dist-packages/IPython',
 'ipython_version': '5.2.2',
 'os_name': 'posix',
 'platform': 'Linux-4.4.0-53-generic-x86_64-with-Ubuntu-16.04-xenial',
 'sys_executable': '/usr/bin/python',
 'sys_platform': 'linux2',
 'sys_version': '2.7.12 (default, Nov 19 2016, 06:48:10) \n[GCC 5.4.0 20160609]'}

{'commit_hash': '5be56c7',
 'commit_source': 'installation',
 'default_encoding': 'ANSI_X3.4-1968',
 'ipython_path': '/usr/local/lib/python3.5/dist-packages/IPython',
 'ipython_version': '5.2.2',
 'os_name': 'posix',
 'platform': 'Linux-4.4.0-53-generic-x86_64-with-Ubuntu-16.04-xenial',
 'sys_executable': '/usr/bin/python3',
 'sys_platform': 'linux',
 'sys_version': '3.5.2 (default, Nov 17 2016, 17:05:23) \n[GCC 5.4.0 20160609]'}

• Python

ipython3
Python 3.5.2 (default, Nov 17 2016, 17:05:23) 
Type "copyright", "credits" or "license" for more information.

IPython 5.2.2 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.

ipython2
Python 2.7.12 (default, Nov 19 2016, 06:48:10) 
Type "copyright", "credits" or "license" for more information.

IPython 5.2.2 -- An enhanced Interactive Python.

[ming2281]

Duplicate with #10289