Using Pexpect with Python 3

Question

After hours of research I have broken down to posting. I am trying to use the Pexpect module with python 3, which I am led to believe is possible from the document page which does say it will run with python 3.2.

Things I have tried: I have tried many different ways of installing including downloading the source and running the command sudo python3 setup.py install. I have also tried installing it with pip and *easy_install* which is what the documentation suggest. It seems that everything goes off with out a hitch until I attempt to import the module in the pyshell. When I type import pexpect I get the error:

class spawn(object): 
File "/usr/local/lib/python3.2/dist-packages/pexpect/init.py", line 286, in spawn
  write_to_stdout = sys.stdout.buffer.write
AttributeError: 'PseudoFile' object has no attribute 'buffer'

I have also tried googleing the error with no luck. And I have tried using python 2.7 and it works fine. I have tried on multiple debian based operating systems: Ubuntu 12.04 and Kali with the same results.

I feel like there is something obvious I am missing, but I just don't see it. Any points in the right direction Or helping me understand the error message would be much appreciated!

Answer 1

There was a bug in Pexpect 3.0 which stopped it working if sys.stdout was replaced before it was imported. It looks like IDLE replaces stdout, so as you've found, it doesn't work in IDLE & Python 3.

The bug has now been fixed. I'll try to get a new version of Pexpect out in the next few days, and then you'll be able to use it from IDLE.