TST: fixed invalid DataFrame() initializations in tests

Author: toobaz

pandas/tests/indexes/test_multi.py

@@ -3066,8 +3066,7 @@ def test_nan_stays_float(self):
         assert pd.isna(idx0.get_level_values(1)).all()
         # the following failed in 0.14.1
         assert pd.isna(idxm.get_level_values(1)[:-1]).all()
-
-        df0 = pd.DataFrame([[1, 2]], index=idx0)
+        df0 = pd.DataFrame([[1, 2]] * 2, index=idx0)
         df1 = pd.DataFrame([[3, 4]], index=idx1)
         dfm = df0 - df1
         assert pd.isna(df0.index.get_level_values(1)).all()

pandas/tests/io/formats/test_style.py

@@ -24,7 +24,7 @@ def setup_method(self, method):
 
         def h(x, foo='bar'):
             return pd.Series(
-                ['color: {foo}'.format(foo=foo)], index=x.index, name=x.name)
+                'color: {foo}'.format(foo=foo), index=x.index, name=x.name)
 
         self.h = h
         self.styler = Styler(self.df)

pandas/tests/reshape/test_reshape.py

@@ -462,7 +462,7 @@ def test_preserve_categorical_dtype(self):
             cidx = pd.CategoricalIndex(list("xyz"), ordered=ordered)
             midx = pd.MultiIndex(levels=[['a'], cidx],
                                  labels=[[0, 0], [0, 1]])
-            df = DataFrame([[10, 11]], index=midx)
+            df = DataFrame([[10, 11]] * 2, index=midx, columns=[0, 1])
 
             expected = DataFrame([[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]],
                                  index=midx, columns=cidx)