Tab completion problems with cell magics

[fperez]

As mentioned by @takluyver in #1732:

One small flaw I've noticed: if you start the Qt console, and type %ti<TAB>, it shows the new %%timeit as an option for tab completion, but it reduces the command at the prompt to the longest common prefix, which is now just %. It ought to be smarter about that. (This isn't specific to Python 3)

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While the problem right now appears only in the Qt console, I'm pondering whether we should also change the policy in the terminal, so that the behavior is uniform as it comes from the completer and we don't need custom client-side logic.

I'll work a bit on it and will see if I can come up with something sensible.

[asmeurer]

I don't think this is just in the Qt console. I just noticed it in the terminal too.

[Carreau]

This was also an issue in notebook, #1829 should fix it.

[ellisonbg]

Fixed in master.

[Carreau]

This seem not to be fixed in qtconsole, reopening.

[fperez]

Yup, confirming the qt bug remains. I'm less confident now that I can fix it b/c it may entail really qt client-side logic. I'm removing myself as assignee just to make it clear that I'm not directly working on a fix.

[Carreau]

Assigning myself think of doing it for 0.13, but if SO have more bandwidth...