Allow empty unions by using whether a type is marked as a union (rath…

…er than the existence of members) to decide whether it is concrete.
pantsbuild · May 16, 2019 · 60d96c2 · 60d96c2
1 parent 2c95f85
commit 60d96c2
Showing 1 changed file with 2 additions and 3 deletions.
diff --git a/src/python/pants/engine/scheduler.py b/src/python/pants/engine/scheduler.py
@@ -202,10  202,9 @@ def add_get_edge(product, subject):
       self._native.lib.tasks_add_get(self._tasks, self._to_type(product), self._to_type(subject))
 
     for the_get in rule.input_gets:
-      union_members = union_rules.get(the_get.subject_declared_type, None)
-      if union_members:
       if getattr(the_get.subject_declared_type, '_is_union', False):
         # If the registered subject type is a union, add Get edges to all registered union members.
-        for union_member in union_members:
         for union_member in union_rules.get(the_get.subject_declared_type, []):
           add_get_edge(the_get.product, union_member)
       else:
         # Otherwise, the Get subject is a "concrete" type, so add a single Get edge.