Updated existing test failures

Author: WillAyd

pandas/tests/frame/test_analytics.py

@@ -1941,12 +1941,9 @@ def test_pct_change(self):
         pnl.iat[1, 1] = np.nan
         pnl.iat[2, 3] = 60
 
-        mask = pnl.isnull()
-
         for axis in range(2):
             expected = pnl.ffill(axis=axis) / pnl.ffill(axis=axis).shift(
                 axis=axis) - 1
-            expected[mask] = np.nan
             result = pnl.pct_change(axis=axis, fill_method='pad')
 
             tm.assert_frame_equal(result, expected)

pandas/tests/frame/test_timeseries.py

@@ -118,7 +118,7 @@ def test_pct_change_shift_over_nas(self):
         df = DataFrame({'a': s, 'b': s})
 
         chg = df.pct_change()
-        expected = Series([np.nan, 0.5, np.nan, 2.5 / 1.5 - 1, .2])
+        expected = Series([np.nan, 0.5, 0., 2.5 / 1.5 - 1, .2])
         edf = DataFrame({'a': expected, 'b': expected})
         assert_frame_equal(chg, edf)
 

pandas/tests/series/test_timeseries.py

@@ -352,7 +352,7 @@ def test_pct_change_shift_over_nas(self):
         s = Series([1., 1.5, np.nan, 2.5, 3.])
 
         chg = s.pct_change()
-        expected = Series([np.nan, 0.5, np.nan, 2.5 / 1.5 - 1, .2])
+        expected = Series([np.nan, 0.5, 0., 2.5 / 1.5 - 1, .2])
         assert_series_equal(chg, expected)
 
     def test_pct_change_periods_freq(self):