YARN-5608. TestAMRMClient.setup() fails with ArrayOutOfBoundsException. Contributed by Daniel Templeton.

(cherry picked from commit f9557127b3660e138cab8d9535a589677809384a)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-client/src/test/java/org/apache/hadoop/yarn/client/api/impl/TestAMRMClient.java

@@ -144,8 +144,13 @@ public class TestAMRMClient {
     yarnClient.start();
 
     // get node info
+    assertTrue("All node managers did not connect to the RM within the "
+        + "allotted 5-second timeout",
+        yarnCluster.waitForNodeManagersToConnect(5000L));
     nodeReports = yarnClient.getNodeReports(NodeState.RUNNING);
-    
+    assertEquals("Not all node managers were reported running",
+        nodeCount, nodeReports.size());
+
     priority = Priority.newInstance(1);
     priority2 = Priority.newInstance(2);
     capability = Resource.newInstance(1024, 1);