COMPAT: compat of scalars on all platforms, xref pandas-dev#11638

Author: jreback

pandas/core/common.py

@@ -1037,16 +1037,16 @@ def _infer_dtype_from_scalar(val):
         dtype = np.bool_
 
     elif is_integer(val):
-        if isinstance(val, int):
-            dtype = np.int64
-        else:
+        if isinstance(val, np.integer):
             dtype = type(val)
+        else:
+            dtype = np.int64
 
     elif is_float(val):
-        if isinstance(val, float):
-            dtype = np.float64
-        else:
+        if isinstance(val, np.floating):
             dtype = type(val)
+        else:
+            dtype = np.float64
 
     elif is_complex(val):
         dtype = np.complex_

pandas/tests/test_common.py

@@ -109,7 +109,7 @@ def test_infer_dtype_from_scalar(self):
                         np.uint64, np.int64 ]:
             data = dtypec(12)
             dtype, val = com._infer_dtype_from_scalar(data)
-            self.assertEqual(dtype, dtypec)
+            self.assertEqual(dtype, type(data))
 
         data = 12
         dtype, val = com._infer_dtype_from_scalar(data)