Add test

libs/langgraph/tests/test_pregel_async.py

@@ -2475,7 +2475,12 @@ async def test_imp_task(checkpointer_name: str) -> None:
         assert mapper_calls == 2
         assert len(tracer.runs) == 1
         assert len(tracer.runs[0].child_runs) == 1
-        assert tracer.runs[0].child_runs[0].name == "graph"
+        entrypoint_run = tracer.runs[0].child_runs[0]
+        assert entrypoint_run.name == "graph"
+        mapper_runs = [r for r in entrypoint_run.child_runs if r.name == "mapper"]
+        assert len(mapper_runs) == 2
+        assert mapper_runs[0].inputs == {"input": 0}
+        assert mapper_runs[1].inputs == {"input": 1}
 
         assert await graph.ainvoke(Command(resume="answer"), thread1) == [
             "00answer",