refactor _create_freshness_response

dbt/adapters/base/impl.py

@@ -1330,25 +1330,11 @@ def calculate_freshness_from_metadata_batch(
                 except Exception:
                     raise MacroResultError(GET_RELATION_LAST_MODIFIED_MACRO_NAME, table)
 
-                if last_modified_val is None:
-                    # Interpret missing value as "infinitely long ago"
-                    max_loaded_at = datetime(1, 1, 1, 0, 0, 0, tzinfo=pytz.UTC)
-                else:
-                    max_loaded_at = _utc(last_modified_val, None, "last_modified")
-
-                snapshotted_at = _utc(snapshotted_at_val, None, "snapshotted_at")
-
-                age = (snapshotted_at - max_loaded_at).total_seconds()
-
-                freshness: FreshnessResponse = {
-                    "max_loaded_at": max_loaded_at,
-                    "snapshotted_at": snapshotted_at,
-                    "age": age,
-                }
+                freshness_response = self._create_freshness_response(last_modified_val, snapshotted_at_val)
                 source_relation_for_result = schema_identifier_to_source[
                     (schema.lower(), identifier.lower())
                 ]
-                freshness_responses[source_relation_for_result] = freshness
+                freshness_responses[source_relation_for_result] = freshness_response
 
         return adapter_response, freshness_responses
 
@@ -1359,11 +1345,27 @@ def calculate_freshness_from_metadata(
     ) -> Tuple[Optional[AdapterResponse], FreshnessResponse]:
         adapter_response, freshness_responses = self.calculate_freshness_from_metadata_batch(
             sources=[source],
-            information_schema=source.information_schema_only(),
             macro_resolver=macro_resolver,
         )
         return adapter_response, list(freshness_responses.values())[0]
 
+    def _create_freshness_response(self, last_modified: Optional[datetime], snapshotted_at: Optional[datetime]) -> FreshnessResponse:
+        if last_modified is None:
+            # Interpret missing value as "infinitely long ago"
+            max_loaded_at = datetime(1, 1, 1, 0, 0, 0, tzinfo=pytz.UTC)
+        else:
+            max_loaded_at = _utc(last_modified, None, "last_modified")
+
+        snapshotted_at = _utc(snapshotted_at, None, "snapshotted_at")
+        age = (snapshotted_at - max_loaded_at).total_seconds()
+        freshness: FreshnessResponse = {
+            "max_loaded_at": max_loaded_at,
+            "snapshotted_at": snapshotted_at,
+            "age": age,
+        }
+
+        return freshness
+
     def pre_model_hook(self, config: Mapping[str, Any]) -> Any:
         """A hook for running some operation before the model materialization
         runs. The hook can assume it has a connection available.