From 15f1947652656433d8d83d58c12332236a6343a2 Mon Sep 17 00:00:00 2001
From: Scott Sanderson <scoutoss@gmail.com>
Date: Mon, 2 Jun 2014 23:22:41 -0400
Subject: [PATCH] BUG: Don't return mostly nans from `get_history` when
 `ffill=False`.

Fixes an issue where, if `ffill=False`, `get_history` would return nans for
every entry in the history frame except the last one.
---
 zipline/history/history_container.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/zipline/history/history_container.py b/zipline/history/history_container.py
index ce2da464..f0b31c4a 100644
--- a/zipline/history/history_container.py
+++ b/zipline/history/history_container.py
@@ -416,6 +416,8 @@ class HistoryContainer(object):
                     # e.g. with leading nans.
                     pass
             digest_frame = digest_frame.ffill()
+
+        if digest_frame is not None:
             return_frame.ix[:-1] = digest_frame.ix[:]
 
         # Get minutes from our buffer panel to build the last row.