[#2341] Initialize slots with empty BitSet in RedisClusterNode's cons…

…tructors (#2852)

* fix(#2341): Initialize slots with empty BitSet in RedisClusterNode's constructors

* test(#2341): Add test cases for slot initialization in RedisClusterNode constructors

* fix(#2341): Initialize RedisClusterNode slots with SlotHash.SLOT_COUNT

* chore(#2341): Adjust the formatting

* test(#2341):Add test cases for hasSameSlotsAs()

* fix(#2341): Clone node2 from node1 using the RedisClusterNode constructor and compare the two clusters with hasSameSlotsAs()

src/main/java/io/lettuce/core/cluster/models/partitions/RedisClusterNode.java

@@ -103,8 +103,11 @@ public RedisClusterNode(RedisURI uri, String nodeId, boolean connected, String s
         this.configEpoch = configEpoch;
         this.replOffset = -1;
 
-        this.slots = new BitSet(slots.length());
-        this.slots.or(slots);
+        this.slots = new BitSet(SlotHash.SLOT_COUNT);
+
+        if (slots != null) {
+            this.slots.or(slots);
+        }
 
         setFlags(flags);
     }
@@ -123,8 +126,9 @@ public RedisClusterNode(RedisClusterNode redisClusterNode) {
         this.replOffset = redisClusterNode.replOffset;
         this.aliases.addAll(redisClusterNode.aliases);
 
-        if (redisClusterNode.slots != null && !redisClusterNode.slots.isEmpty()) {
-            this.slots = new BitSet(SlotHash.SLOT_COUNT);
+        this.slots = new BitSet(SlotHash.SLOT_COUNT);
+
+        if (redisClusterNode.slots != null) {
             this.slots.or(redisClusterNode.slots);
         }
 

src/test/java/io/lettuce/core/cluster/models/partitions/RedisClusterNodeUnitTests.java

@@ -3,6 +3,9 @@
 import static org.assertj.core.api.Assertions.*;
 
 import java.util.Arrays;
+import java.util.BitSet;
+import java.util.Collections;
+import java.util.HashSet;
 
 import org.junit.jupiter.api.Test;
 
@@ -16,6 +19,88 @@
  */
 class RedisClusterNodeUnitTests {
 
+    @Test
+    void shouldCreateNodeWithEmptySlots() {
+
+        BitSet slots = new BitSet();
+        RedisClusterNode node = new RedisClusterNode(RedisURI.create("localhost", 6379), "1", true, null, 0, 0, 0, slots,
+                Collections.emptySet());
+
+        assertThat(node.getSlots()).isEmpty();
+        assertThat(node.getSlots()).isNotNull();
+    }
+
+    @Test
+    void shouldCreateNodeWithNonEmptySlots() {
+
+        BitSet slots = new BitSet();
+        slots.set(1);
+        slots.set(2);
+        RedisClusterNode node = new RedisClusterNode(RedisURI.create("localhost", 6379), "1", true, null, 0, 0, 0, slots,
+                Collections.emptySet());
+
+        assertThat(node.getSlots()).containsExactly(1, 2);
+    }
+
+    @Test
+    void shouldCopyNodeWithEmptySlots() {
+
+        BitSet slots = new BitSet();
+        RedisClusterNode originalNode = new RedisClusterNode(RedisURI.create("localhost", 6379), "1", true, null, 0, 0, 0,
+                slots, Collections.emptySet());
+
+        RedisClusterNode copiedNode = new RedisClusterNode(originalNode);
+
+        assertThat(copiedNode.getSlots()).isEmpty();
+        assertThat(copiedNode.getSlots()).isNotNull();
+    }
+
+    @Test
+    void shouldCopyNodeWithNonEmptySlots() {
+
+        BitSet slots = new BitSet();
+        slots.set(1);
+        slots.set(2);
+        RedisClusterNode originalNode = new RedisClusterNode(RedisURI.create("localhost", 6379), "1", true, null, 0, 0, 0,
+                slots, Collections.emptySet());
+
+        RedisClusterNode copiedNode = new RedisClusterNode(originalNode);
+
+        assertThat(copiedNode.getSlots()).containsExactly(1, 2);
+    }
+
+    @Test
+    public void testHasSameSlotsAs() {
+
+        BitSet emptySlots = new BitSet(SlotHash.SLOT_COUNT);
+        emptySlots.set(1);
+        emptySlots.set(2);
+
+        RedisClusterNode node1 = new RedisClusterNode(RedisURI.create("localhost", 6379), "nodeId1", true, "slaveOf", 0L, 0L,
+                0L, emptySlots, new HashSet<>());
+
+        RedisClusterNode node2 = new RedisClusterNode(node1);
+
+        assertThat(node1.hasSameSlotsAs(node2)).isTrue();
+    }
+
+    @Test
+    public void testHasDifferentSlotsAs() {
+
+        BitSet slots1 = new BitSet(SlotHash.SLOT_COUNT);
+        slots1.set(1);
+
+        BitSet slots2 = new BitSet(SlotHash.SLOT_COUNT);
+        slots2.set(2);
+
+        RedisClusterNode node1 = new RedisClusterNode(RedisURI.create("localhost", 6379), "nodeId1", true, "slaveOf", 0L, 0L,
+                0L, slots1, new HashSet<>());
+        RedisClusterNode node2 = new RedisClusterNode(RedisURI.create("localhost", 6379), "nodeId2", true, "slaveOf", 0L, 0L,
+                0L, slots2, new HashSet<>());
+
+        assertThat(node1.hasSameSlotsAs(node2)).isFalse();
+    }
+
     @Test
     void shouldCopyNode() {