Fix mypy test

core/dbt/contracts/graph/unparsed.py

@@ -167,7 +167,11 @@ class Time(dbtClassMixin, Mergeable):
     period: Optional[TimePeriod] = None
 
     def exceeded(self, actual_age: float) -> bool:
-        kwargs = {self.period.plural(): self.count}
+        if self.period is None:
+            return False
+        if self.count is None:
+            return False
+        kwargs: Dict[str, int] = {self.period.plural(): self.count}
         difference = timedelta(**kwargs).total_seconds()
         return actual_age > difference
 

core/dbt/parser/sources.py

@@ -348,15 +348,15 @@ def get_unused_msg(
 def merge_freshness_time_thresholds(
     base: Optional[Time], update: Optional[Time]
 ) -> Optional[Time]:
-    if base is None and update is None:
-        return None
+    if base is not None and update is not None:
+        return base.merged(update)
     elif base is None and update is not None:
         return update
     elif base is not None and update is None:
         return base
     else:
-        # base and update are not none
-        return base.merged(update)
+        # base and update are none
+        return None
 
 
 def merge_freshness(