Reinstate testUnhealthyNodesGetsRemoved for stateless (#95404)

Author: DaveCTurner

server/src/test/java/org/elasticsearch/cluster/coordination/AtomicRegisterCoordinatorTests.java

@@ -42,13 +42,6 @@
 
 @TestLogging(reason = "these tests do a lot of log-worthy things but we usually don't care", value = "org.elasticsearch:FATAL")
 public class AtomicRegisterCoordinatorTests extends CoordinatorTests {
-    @Override
-    @AwaitsFix(bugUrl = "ES-5645")
-    public void testUnhealthyNodesGetsRemoved() {
-        // This test checks that the voting configuration shrinks after a node is removed from the cluster
-        // TODO: rewrite this test without taking into account the final voting configuration
-    }
-
     @Override
     @AwaitsFix(bugUrl = "ES-5645")
     public void testLeaderDisconnectionWithDisconnectEventDetectedQuickly() {
@@ -147,6 +140,12 @@ public void testCannotJoinClusterWithDifferentUUID() {
         // TODO: add more checks to avoid forming a mixed cluster between register based and traditional clusters
     }
 
+    @Override
+    public void testUnhealthyNodesGetsRemoved() {
+        // the test still applies with an atomic register, except for the assertions about the voting configuration
+        testUnhealthyNodesGetsRemoved(false);
+    }
+
     @Override
     public void testJoiningNodeReceivesFullState() {
         try (Cluster cluster = new Cluster(randomIntBetween(1, 5))) {

server/src/test/java/org/elasticsearch/cluster/coordination/CoordinatorTests.java

@@ -123,6 +123,10 @@ public void testDoesNotElectNonMasterNode() {
     }
 
     public void testUnhealthyNodesGetsRemoved() {
+        testUnhealthyNodesGetsRemoved(true);
+    }
+
+    protected void testUnhealthyNodesGetsRemoved(boolean verifyVotingConfiguration) {
         AtomicReference<StatusInfo> healthStatusInfo = new AtomicReference<>(new StatusInfo(HEALTHY, "healthy-info"));
         try (Cluster cluster = new Cluster(3)) {
             cluster.runRandomly();
@@ -148,7 +152,7 @@ public void testUnhealthyNodesGetsRemoved() {
                     + 2 * 2 * DEFAULT_CLUSTER_STATE_UPDATE_DELAY
             );
 
-            {
+            if (verifyVotingConfiguration) {
                 assertThat(leader.coordinator.getMode(), is(Mode.LEADER));
                 final VotingConfiguration lastCommittedConfiguration = leader.getLastAppliedClusterState().getLastCommittedConfiguration();
                 assertThat(
@@ -190,7 +194,8 @@ public void testUnhealthyNodesGetsRemoved() {
                     // then wait for the followup reconfiguration
                     + DEFAULT_CLUSTER_STATE_UPDATE_DELAY
             );
-            {
+
+            if (verifyVotingConfiguration) {
                 final ClusterNode newLeader = cluster.getAnyLeader();
                 final VotingConfiguration lastCommittedConfiguration = newLeader.getLastAppliedClusterState()
                     .getLastCommittedConfiguration();