BUG: Dataframe constructor when given dict with None value

BUG: Dataframe constructor when given dict with None value

Author: brandonmburroughs

doc/source/whatsnew/v0.19.1.txt

@@ -42,6 +42,6 @@ Bug Fixes
 
 
 
-
+- Bug in ``pd.DataFrame`` where constructor fails when given dict with ``None`` value (:issue:`14381`)
 - Bug in ``pd.concat`` where names of the ``keys`` were not propagated to the resulting ``MultiIndex`` (:issue:`14252`)
 - Bug in ``MultiIndex.set_levels`` where illegal level values were still set after raising an error (:issue:`13754`)

pandas/core/frame.py

@@ -5693,6 +5693,8 @@ def _homogenize(data, index, dtype=None):
                 else:
                     v = dict(v)
                 v = lib.fast_multiget(v, oindex.values, default=NA)
+            elif v is None:
+                v = np.nan
             v = _sanitize_array(v, index, dtype=dtype, copy=False,
                                 raise_cast_failure=False)
 

pandas/tests/frame/test_constructors.py

@@ -259,6 +259,12 @@ def test_constructor_dict(self):
         frame = DataFrame({'A': [], 'B': []}, columns=['A', 'B'])
         self.assert_index_equal(frame.index, Index([], dtype=np.int64))
 
+        # GH 14381
+        # Dict with None value
+        frame_none = DataFrame(dict(a=None), index=[0])
+        frame_nan = DataFrame(dict(a=np.nan), index=[0])
+        tm.assert_frame_equal(frame_none, frame_nan)
+
         # GH10856
         # dict with scalar values should raise error, even if columns passed
         with tm.assertRaises(ValueError):