Fixed handling of empty Time Freq Support (#996)

* Fixed factory regarding time freq support

* Revert "Fixed factory regarding time freq support"

This reverts commit 2275661.

* Fixed nullptr handling of timefreq support

* Fixed unit setting when None

* Added tests

* Workaround to avoid throwing when retrieving no tf support

* Do not raise exception only if support not present

* breaks retro due to C++ changes

src/ansys/dpf/core/collection.py

@@ -383,14 +383,29 @@ def _get_time_freq_support(self):
             capi=data_processing_capi.DataProcessingCAPI,
             grpcapi=data_processing_grpcapi.DataProcessingGRPCAPI,
         )
+        internal_obj = None
+        # LegacyGrpcServer throws UNAVAILABLE when retrieving nullptr
+        # This is all to obtain a None instead of throwing
+        import ansys.dpf.gate.errors as err
+
+        try:
+            internal_obj = self._api.collection_get_support(self, "time")
+        except err.DPFServerException as e:
+            str_to_ignore = "The collection does not have a support."
+            if str_to_ignore not in str(e):
+                raise e
+        if not internal_obj:
+            return None
+
         support = object_handler.ObjHandler(
             data_processing_api=data_api,
-            internal_obj=self._api.collection_get_support(self, "time"),
+            internal_obj=internal_obj,
             server=self._server,
         )
         support_api = self._server.get_api_for_type(
             capi=support_capi.SupportCAPI, grpcapi=support_grpcapi.SupportGRPCAPI
         )
+
         time_freq = support_api.support_get_as_time_freq_support(support)
         res = TimeFreqSupport(time_freq_support=time_freq, server=self._server)
         return res

src/ansys/dpf/core/fields_container_factory.py

@@ -62,7 +62,8 @@ def over_time_freq_fields_container(fields, time_freq_unit=None, server=None):
             len(fields), location=locations.time_freq, server=server
         )
         time_freq_field.append(time_freq, 1)
-        time_freq_field.unit = time_freq_unit
+        if time_freq_unit:
+            time_freq_field.unit = time_freq_unit
         time_freq_support = TimeFreqSupport(server=server)
         time_freq_support.time_frequencies = time_freq_field
         fc.time_freq_support = time_freq_support

tests/test_fieldscontainer.py

@@ -503,10 +503,31 @@ def test_dot_operator_fields_container():
     assert np.allclose(out[0].data, -field.data)
 
 
+def test_fields_container_factory_with_dict():
+    field1 = dpf.Field()
+    field1.data = [1, 2, 3]
+    field2 = dpf.Field()
+    field2.data = [2, 3, 4]
+    fields_container = dpf.fields_container_factory.over_time_freq_fields_container(
+        fields={0.1: field1, 0.2: field2}
+    )
+
+    assert fields_container[0].unit == ""
+
+
 def test_fields_container_get_time_scoping(server_type, disp_fc):
     freq_scoping = disp_fc.get_time_scoping()
     assert freq_scoping.size == 1
 
 
+@pytest.mark.skipif(
+    not conftest.SERVERS_VERSION_GREATER_THAN_OR_EQUAL_TO_7_0, reason="Available for servers >=7.0"
+)
+def test_fields_container_empty_tf_support(server_type):
+    fields_container = dpf.FieldsContainer(server=server_type)
+
+    assert fields_container.time_freq_support == None
+
+
 if __name__ == "__main__":
     test_add_field_by_time_id()