[extended] Fix LeaderElectionRecord.equals null renewTime comparison

extended/src/main/java/io/kubernetes/client/extended/leaderelection/LeaderElectionRecord.java

@@ -139,7 +139,7 @@ public boolean equals(Object o) {
       if (!acquireTime.equals(that.acquireTime)) return false;
     }
     if (renewTime == null) {
-      return that.holderIdentity == null;
+      return that.renewTime == null;
     }
     return renewTime.equals(that.renewTime);
   }

extended/src/test/java/io/kubernetes/client/extended/leaderelection/LeaderElectionRecordTest.java

@@ -0,0 +1,48 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+Licensed 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 io.kubernetes.client.extended.leaderelection;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.Date;
+import org.junit.jupiter.api.Test;
+
+class LeaderElectionRecordTest {
+
+  // Two records that differ only by having a null renewTime must still be equal to each
+  // other when every other field (including renewTime, which is null on both) matches.
+  @Test
+  void equalWhenRenewTimeIsNullOnBoth() {
+    Date acquireTime = new Date(1000L);
+    LeaderElectionRecord a = new LeaderElectionRecord("holder", 15, acquireTime, null, 3);
+    LeaderElectionRecord b = new LeaderElectionRecord("holder", 15, acquireTime, null, 3);
+
+    assertThat(a).isEqualTo(b);
+    assertThat(b).isEqualTo(a);
+    assertThat(a.hashCode()).isEqualTo(b.hashCode());
+  }
+
+  // When one record has a null renewTime and the other does not, they must be unequal,
+  // regardless of the holderIdentity value.
+  @Test
+  void notEqualWhenOnlyOneRenewTimeIsNull() {
+    Date acquireTime = new Date(1000L);
+    Date renewTime = new Date(2000L);
+    LeaderElectionRecord nullRenew = new LeaderElectionRecord("holder", 15, acquireTime, null, 3);
+    LeaderElectionRecord withRenew =
+        new LeaderElectionRecord("holder", 15, acquireTime, renewTime, 3);
+
+    assertThat(nullRenew).isNotEqualTo(withRenew);
+    assertThat(withRenew).isNotEqualTo(nullRenew);
+  }
+}