From 63f574738379226e5e57399d1cd9e399ef0ce6b6 2015-01-17 01:14:27
From: Min RK <benjaminrk@gmail.com>
Date: 2015-01-17 01:14:27
Subject: [PATCH] handle missing stream name in nbformat conversion

It was sometimes possible for this key to be absent.
Even though that's never been officially valid,
it happened, so might as well handle it.
---

diff --git a/IPython/nbformat/v4/convert.py b/IPython/nbformat/v4/convert.py
index 1e9e65e..a6c3f36 100644
--- a/IPython/nbformat/v4/convert.py
+++ b/IPython/nbformat/v4/convert.py
@@ -186,7 +186,7 @@ def upgrade_output(output):
     elif output['output_type'] == 'pyerr':
         output['output_type'] = 'error'
     elif output['output_type'] == 'stream':
-        output['name'] = output.pop('stream')
+        output['name'] = output.pop('stream', 'stdout')
     return output
 
 def downgrade_output(output):