Update PR#8641: add unit tests

Author: weizhouapache

server/src/main/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscoverer.java

@@ -490,7 +490,7 @@ public HostVO createHostVOForConnectedAgent(HostVO host, StartupCommand[] cmd) {
         return _resourceMgr.fillRoutingHostVO(host, ssCmd, getHypervisorType(), host.getDetails(), null);
     }
 
-    private boolean isHostOsCompatibleWithOtherHost(String hostOsInCluster, String hostOs) {
+    protected boolean isHostOsCompatibleWithOtherHost(String hostOsInCluster, String hostOs) {
         if (hostOsInCluster.equalsIgnoreCase(hostOs)) {
             return true;
         }

server/src/test/java/com/cloud/hypervisor/kvm/discoverer/LibvirtServerDiscovererTest.java

@@ -0,0 +1,54 @@
+//
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+//
+
+package com.cloud.hypervisor.kvm.discoverer;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Spy;
+import org.mockito.junit.MockitoJUnitRunner;
+
+@RunWith(MockitoJUnitRunner.class)
+public class LibvirtServerDiscovererTest {
+
+    @Spy
+    private LibvirtServerDiscoverer libvirtServerDiscoverer;
+
+    @Test
+    public void validateCompatibleOses() {
+        validateCompatibleOs("Rocky Linux", "Rocky Linux", true);
+        validateCompatibleOs("Rocky", "Rocky Linux", true);
+        validateCompatibleOs("Red", "Red Hat Enterprise Linux", true);
+        validateCompatibleOs("Oracle", "Oracle Linux Server", true);
+        validateCompatibleOs("Rocky Linux", "Red Hat Enterprise Linux", true);
+        validateCompatibleOs("AlmaLinux", "Red Hat Enterprise Linux", true);
+
+        validateCompatibleOs("Windows", "Rocky Linux", false);
+        validateCompatibleOs("SUSE", "Rocky Linux", false);
+    }
+
+    private void validateCompatibleOs(String hostOsInCluster, String hostOs, boolean expected) {
+        if (expected) {
+            Assert.assertTrue(libvirtServerDiscoverer.isHostOsCompatibleWithOtherHost(hostOsInCluster, hostOs));
+        } else {
+            Assert.assertFalse(libvirtServerDiscoverer.isHostOsCompatibleWithOtherHost(hostOsInCluster, hostOs));
+        }
+    }
+}