Breaking change: raise TypeError when convert non-timedelta to Duration, or convert non-datetime to Timestamp in python proto. (Original code may raise ArributeError)

https://protobuf.dev/news/2025-09-19/#python-type-error-timestamp-duration

PiperOrigin-RevId: 824803296

Author: anandolee

python/google/protobuf/internal/duration_test.py

@@ -104,7 +104,7 @@ def test_duration_add_annotation(self):
 
   def test_assign_datetime_to_duration(self):
     message = well_known_types_test_pb2.WKTMessage()
-    with self.assertRaises((TypeError, AttributeError)):
+    with self.assertRaises((TypeError)):
       message.optional_duration = datetime.datetime.now()
 
 

python/google/protobuf/internal/timestamp_test.py

@@ -111,7 +111,7 @@ def test_timestamp_add_annotation(self):
 
   def test_assign_duration_to_timestamp(self):
     message = well_known_types_test_pb2.WKTMessage()
-    with self.assertRaises((TypeError, AttributeError)):
+    with self.assertRaises((TypeError)):
       message.optional_timestamp = datetime.timedelta(microseconds=123)
 
 

python/google/protobuf/internal/well_known_types.py

@@ -279,6 +279,13 @@ def FromDatetime(self, dt):
     # manipulated into a long value of seconds.  During the conversion from
     # struct_time to long, the source date in UTC, and so it follows that the
     # correct transformation is calendar.timegm()
+    if type(dt).__name__ != 'datetime' and not isinstance(
+        dt, datetime.datetime
+    ):
+      raise TypeError(
+          'Fail to convert to Timestamp. Expected a datetime object '
+          'got {0}'.format(type(dt).__name__)
+      )
     try:
       seconds = calendar.timegm(dt.utctimetuple())
       nanos = dt.microsecond * _NANOS_PER_MICROSECOND
@@ -445,6 +452,13 @@ def ToTimedelta(self) -> datetime.timedelta:
 
   def FromTimedelta(self, td):
     """Converts timedelta to Duration."""
+    if type(td).__name__ != 'timedelta' and not isinstance(
+        td, datetime.timedelta
+    ):
+      raise TypeError(
+          'Fail to convert to Duration. Expected a timedelta object '
+          'got {0}'.format(type(td).__name__)
+      )
     try:
       self._NormalizeDuration(
           td.seconds + td.days * _SECONDS_PER_DAY,

python/google/protobuf/internal/well_known_types_test.py

@@ -540,10 +540,10 @@ def testInvalidTimestamp(self):
     self.assertRaisesRegex(ValueError, 'Timestamp is not valid',
                            message.FromSeconds, -62135596801)
     msg = well_known_types_test_pb2.WKTMessage()
-    with self.assertRaises((TypeError, AttributeError)):
+    with self.assertRaises((TypeError)):
       msg.optional_timestamp = 1
 
-    with self.assertRaises((TypeError, AttributeError)):
+    with self.assertRaises((TypeError)):
       msg2 = well_known_types_test_pb2.WKTMessage(optional_timestamp=1)
 
     with self.assertRaises(TypeError):