From c3b429bdd87e76214d41ded98a11b74d48e1949a 2013-04-12 23:14:05
From: Min RK <benjaminrk@gmail.com>
Date: 2013-04-12 23:14:05
Subject: [PATCH] Merge pull request #3162 from ivanov/output-stream-kwarg

adding stream kwarg to current.new_output

This was missing, and made unnecessarily clunky to create output cells
of stream type using the nbformat API.

Before this commit, you had to do something like

    from IPython.nbformat import current as c
    output = c.new_output('stream', the_text)
    output['stream'] = 'stdout'

after this commit

    from IPython.nbformat import current as c
    output = c.new_output('stream', the_text, stream='stdout')

and actually, that stream= argument defaults to 'stdout' if it isn't given.

I modified a test that will break if this functionality is ever removed.
---

diff --git a/IPython/nbformat/v3/nbbase.py b/IPython/nbformat/v3/nbbase.py
index f4e312b..c8089d7 100644
--- a/IPython/nbformat/v3/nbbase.py
+++ b/IPython/nbformat/v3/nbbase.py
@@ -53,7 +53,7 @@ def from_dict(d):
 def new_output(output_type=None, output_text=None, output_png=None,
     output_html=None, output_svg=None, output_latex=None, output_json=None,
     output_javascript=None, output_jpeg=None, prompt_number=None,
-    etype=None, evalue=None, traceback=None):
+    etype=None, evalue=None, traceback=None, stream=None):
     """Create a new code cell with input and output"""
     output = NotebookNode()
     if output_type is not None:
@@ -89,6 +89,9 @@ def new_output(output_type=None, output_text=None, output_png=None,
         if traceback is not None:
             output.traceback = [unicode(frame) for frame in list(traceback)]
 
+    if output_type == u'stream':
+        output.stream = 'stdout' if stream is None else unicode(stream)
+
     return output
 
 
diff --git a/IPython/nbformat/v3/tests/nbexamples.py b/IPython/nbformat/v3/tests/nbexamples.py
index efdd38e..fa9b5cf 100644
--- a/IPython/nbformat/v3/tests/nbexamples.py
+++ b/IPython/nbformat/v3/tests/nbexamples.py
@@ -93,6 +93,7 @@ ws.cells.append(new_code_cell(
         output_text='foo\rbar\r\n'
     ),new_output(
         output_type=u'stream',
+        stream='stderr',
         output_text='\rfoo\rbar\n'
     )]
 ))