From 68e44353cea0a1006ab9fbdd6a4c8ada684dc229 Mon Sep 17 00:00:00 2001
From: Joe Jevnik <joejev@gmail.com>
Date: Tue, 18 Nov 2014 15:23:10 -0500
Subject: [PATCH] MAINT: Make RandomWalkSource accept the standard daily
 instead of day for the frequency

---
 tests/test_sources.py        | 2 +-
 zipline/sources/simulated.py | 9 +++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/tests/test_sources.py b/tests/test_sources.py
index 506887e1..a3590cfa 100644
--- a/tests/test_sources.py
+++ b/tests/test_sources.py
@@ -113,7 +113,7 @@ class TestRandomWalkSource(TestCase):
         end = pd.Timestamp('1992-01-01', tz='UTC')
         source = RandomWalkSource(start_prices=start_prices,
                                   calendar=calendar_nyse, start=start,
-                                  end=end, freq='day')
+                                  end=end, freq='daily')
         self.assertIsInstance(source.start, pd.lib.Timestamp)
         self.assertIsInstance(source.end, pd.lib.Timestamp)
 
diff --git a/zipline/sources/simulated.py b/zipline/sources/simulated.py
index 5e348d97..f7b6ec49 100644
--- a/zipline/sources/simulated.py
+++ b/zipline/sources/simulated.py
@@ -31,6 +31,8 @@ class RandomWalkSource(DataSource):
     user-defined frequencies (e.g. minutely).
 
     """
+    VALID_FREQS = frozenset(('daily', 'minute'))
+
     def __init__(self, start_prices=None, freq='minute', start=None,
                  end=None, calendar=calendar_nyse):
         """
@@ -40,7 +42,7 @@ class RandomWalkSource(DataSource):
                  Default: {0: 100, 1: 500}
             freq : str <default='minute'>
                  Emits events according to freq.
-                 Can be 'day' or 'minute'
+                 Can be 'daily' or 'minute'
             start : datetime <default=start of calendar>
                  Start dt to emit events.
             end : datetime <default=end of calendar>
@@ -61,6 +63,9 @@ class RandomWalkSource(DataSource):
         self.arg_string = hash_args(start_prices, freq, start, end,
                                     calendar.__name__)
 
+        if freq not in self.VALID_FREQS:
+            raise ValueError('%s not in %s' % (freq, self.VALID_FREQS))
+
         self.freq = freq
         if start_prices is None:
             self.start_prices = {0: 100,
@@ -134,7 +139,7 @@ class RandomWalkSource(DataSource):
                     for event in self._gen_events(cur_prices, current_dt):
                         yield event
                     current_dt += timedelta(minutes=1)
-            elif self.freq == 'day':
+            elif self.freq == 'daily':
                 # Emit one signal per day at close
                 for event in self._gen_events(cur_prices, close_dt):
                     yield event