COMPAT: remove deprecation warnings for numpy 1.14

COMPAT: sas7bdat warning of unclosed file with 0 rows

Author: jreback

pandas/core/groupby.py

@@ -1913,7 +1913,10 @@ def size(self):
         """
         ids, _, ngroup = self.group_info
         ids = _ensure_platform_int(ids)
-        out = np.bincount(ids[ids != -1], minlength=ngroup or None)
+        if ngroup:
+            out = np.bincount(ids[ids != -1], minlength=ngroup)
+        else:
+            out = ids
         return Series(out,
                       index=self.result_index,
                       dtype='int64')

pandas/io/sas/sas7bdat.py

@@ -596,6 +596,7 @@ def read(self, nrows=None):
             nrows = self.row_count
 
         if len(self.column_types) == 0:
+            self.close()
             raise EmptyDataError("No columns to parse from file")
 
         if self._current_row_in_file_index >= self.row_count: