added a test for Timestamp

Author: discort

pandas/tseries/tests/test_timeseries.py

@@ -4858,6 +4858,15 @@ def test_is_leap_year(self):
         self.assertFalse(pd.NaT.is_leap_year)
         self.assertIsInstance(pd.NaT.is_leap_year, bool)
 
+    def test_round_nat(self):
+        # GH14940
+        ts = Timestamp('nat')
+        print(dir(ts))
+        for method in ["round", "floor", "ceil"]:
+            round_method = getattr(ts, method)
+            for freq in ["s", "5s", "min", "5min", "h", "5h"]:
+                self.assertIs(round_method(freq), ts)
+
 
 class TestSlicing(tm.TestCase):
     def test_slice_year(self):

pandas/tslib.pyx

@@ -885,7 +885,12 @@ def _make_nan_func(func_name):
     f.__name__ = func_name
     return f
 
+
+# GH14940
+_round_methods = ['round', 'floor', 'ceil']
+
 _nat_methods = ['date', 'now', 'replace', 'to_pydatetime', 'today']
+_nat_methods.extend(_round_methods)
 
 _nan_methods = ['weekday', 'isoweekday', 'total_seconds']
 
@@ -895,7 +900,7 @@ _implemented_methods.extend(_nan_methods)
 
 for _method_name in _nat_methods:
     # not all methods exist in all versions of Python
-    if hasattr(NaTType, _method_name):
+    if hasattr(NaTType, _method_name) or _method_name in _round_methods:
         setattr(NaTType, _method_name, _make_nat_func(_method_name))
 
 for _method_name in _nan_methods: