Separate InputSplitter for transforming whole cells

[takluyver]

This allows cell magics to include blank lines once again (#3178).

InteractiveShell now has two input splitters:

• input_splitter is used to determine when a block of input is complete, so you can use a cell magic in the terminal by leaving a blank line at the end.
• input_transformer_manager is used to transform whole cells, so cell magics affect the whole of their cell.

I removed the similar concept of 'input modes' for InputSplitter, because it was bound to get conflated, and it made the code rather hard to follow.

[takluyver]

I'm going to be away for a couple of days, so if this needs any changes, I'll get onto them when I'm back. But I've verified that it fixes the issue with cell magics containing blank lines.

[minrk]

Is there a test for the regression? I don't see a test for a cell magic with an empty line.

[takluyver]

The modified CellModeCellMagics test case covers this in a slightly
sideways manner. Specifically, it tests that the input splitter used to
transform whole cells doesn't think the input is complete after a blank
line. A more explicit test for code after a blank line might be worthwhile.

On 20 April 2013 20:34, Min RK notifications@github.com wrote:

Is there a test for the regression? I don't see a test for a cell magic
with an empty line.

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Reply to this email directly or view it on GitHubhttps://github.com//pull/3203#issuecomment-16709946
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[markusbaden]

This fixes the problem for me, see gist on nbviewer, thanks for the fast fix!

[minrk]

Since this is important and looks clean enough, I will go ahead and merge. We can add more tests in a later PR.