From ab1a23526ddca49b824d2abc0431109d08f8a552 Mon Sep 17 00:00:00 2001
From: Eddie Hebert <ehebert@quantopian.com>
Date: Wed, 24 Apr 2013 16:17:31 -0400
Subject: [PATCH] BUG: Use last trading day for last successful date message.

market_open member does not exist on TradingEnvironment.
---
 zipline/finance/trading.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/zipline/finance/trading.py b/zipline/finance/trading.py
index 6502a68f..4b356565 100644
--- a/zipline/finance/trading.py
+++ b/zipline/finance/trading.py
@@ -176,7 +176,7 @@ class TradingEnvironment(object):
         if next_open is None:
             raise Exception(
                 "Attempt to backtest beyond available history. \
-Last successful date: %s" % self.market_open)
+Last successful date: %s" % self.last_trading_day)
 
         return self.get_open_and_close(next_open)