Original Launchpad bug 508971: https://bugs.launchpad.net/ipython/+bug/508971
Reported by: fdo.perez (Fernando Perez).

This bug is a follow-up of:

https://bugs.launchpad.net/ipython/+bug/362142

which is now closed and split into several more specific reports. See the above for extra background.

The main points brought up by Brian:

Our test suite is still quite fragile and difficult to debug when things go wrong (case in point, your recent bug report about the history being dumped to the screen). If we can get the dpendency issues worked out (to isolate twisted and nose) I think most of this fragility is localized to the nose extension that handles the one time IPython shell. I think our test infrastructure has to be completely independent of our main IPython code (the testing infrastucture should never do "from IPython import ...").

At some point, we figured out how we could enable the writing of IPython doctests without the nose extension (do you remember how this can be done?). As I remember we talked about using this idea along with pexpect to isolate the running IPython to another process.

Jorgen noted:

I think using pexpect requires some research if you want to keep the the
tests running on windows.

Brian's reply:
Yes, this is a huge problem - pexpect doesn't work on Windows...

We should check with the Sage folks, I know at one point, they were working on a windows port of pexpect called wexpect.

Twisted does have many of the same capabilities that pexpect has for working with external processes. That might be our best bet.