Clarify why new stream entries aren't deleted with XDELEX (#4218)

* Improve naming for status 2 in StreamEntryDeletionResult

* Clarify why new stream entries aren't deleted with XDELEX

* Fix formatting of StreamEntryDeletionResultTest

Author: uglide

src/main/java/redis/clients/jedis/resps/StreamEntryDeletionResult.java

@@ -5,8 +5,7 @@
  * <ul>
  * <li>NOT_FOUND (-1): ID doesn't exist in stream</li>
  * <li>DELETED (1): Entry was deleted/acknowledged and deleted</li>
- * <li>ACKNOWLEDGED_NOT_DELETED (2): Entry was acknowledged but not deleted (still has dangling
- * references)</li>
+ * <li>NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED (2): Entry wasn't deleted.</li>
  * </ul>
  */
 public enum StreamEntryDeletionResult {
@@ -28,10 +27,13 @@ public enum StreamEntryDeletionResult {
   DELETED(1),
 
   /**
-   * The entry was acknowledged but not deleted because it still has dangling references in other
-   * consumer groups' pending entry lists.
+   * The entry was not deleted due to one of the following reasons:
+   * <ul>
+   * <li>For XDELEX: The entry was not acknowledged by any consumer group</li>
+   * <li>For XACKDEL: The entry still has pending references in other consumer groups</li>
+   * </ul>
    */
-  ACKNOWLEDGED_NOT_DELETED(2);
+  NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED(2);
 
   private final int code;
 
@@ -60,7 +62,7 @@ public static StreamEntryDeletionResult fromCode(int code) {
       case 1:
         return DELETED;
       case 2:
-        return ACKNOWLEDGED_NOT_DELETED;
+        return NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED;
       default:
         throw new IllegalArgumentException("Unknown stream entry deletion result code: " + code);
     }

src/test/java/redis/clients/jedis/commands/jedis/StreamsBinaryCommandsTest.java

@@ -457,7 +457,7 @@ public void testXdelexWithConsumerGroups() {
     List<StreamEntryDeletionResult> results = jedis.xdelex(STREAM_KEY_1, StreamDeletionPolicy.ACKNOWLEDGED, readId1, readId2);
     assertThat(results, hasSize(2));
     assertEquals(StreamEntryDeletionResult.DELETED, results.get(0)); // id1 was acknowledged
-    assertEquals(StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED, results.get(1)); // id2 not acknowledged
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED, results.get(1)); // id2 not acknowledged
 
     // Verify only acknowledged entry was deleted
     assertEquals(1L, jedis.xlen(STREAM_KEY_1));

src/test/java/redis/clients/jedis/commands/unified/StreamsBinaryCommandsTestBase.java

@@ -474,7 +474,7 @@ public void testXdelexWithConsumerGroups() {
     List<StreamEntryDeletionResult> results = jedis.xdelex(STREAM_KEY_1, StreamDeletionPolicy.ACKNOWLEDGED, readId1, readId2);
     assertThat(results, hasSize(2));
     assertEquals(StreamEntryDeletionResult.DELETED, results.get(0)); // id1 was acknowledged
-    assertEquals(StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED, results.get(1)); // id2 not acknowledged
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED, results.get(1)); // id2 not acknowledged
 
     // Verify only acknowledged entry was deleted
     assertEquals(1L, jedis.xlen(STREAM_KEY_1));

src/test/java/redis/clients/jedis/commands/unified/StreamsCommandsTestBase.java

@@ -13,9 +13,7 @@
 import redis.clients.jedis.params.XPendingParams;
 import redis.clients.jedis.params.XReadGroupParams;
 import redis.clients.jedis.params.XTrimParams;
-import redis.clients.jedis.resps.StreamEntry;
-import redis.clients.jedis.resps.StreamPendingEntry;
-import redis.clients.jedis.resps.StreamEntryDeletionResult;
+import redis.clients.jedis.resps.*;
 
 import java.util.HashMap;
 import java.util.List;
@@ -760,8 +758,9 @@ public void xdelexWithConsumerGroups() {
       StreamDeletionPolicy.ACKNOWLEDGED, readId1, readId2);
     assertThat(results, hasSize(2));
     assertEquals(StreamEntryDeletionResult.DELETED, results.get(0)); // id1 was acknowledged
-    assertEquals(StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED, results.get(1)); // id2 not
-                                                                                      // acknowledged
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED,
+      results.get(1)); // id2 not
+    // acknowledged
 
     // Verify only acknowledged entry was deleted
     assertEquals(1L, jedis.xlen(STREAM_KEY_1));
@@ -778,4 +777,44 @@ public void xdelexEmptyStream() {
     assertThat(results, hasSize(1));
     assertEquals(StreamEntryDeletionResult.NOT_FOUND, results.get(0));
   }
+
+  @Test
+  @SinceRedisVersion("8.1.240")
+  public void xdelexNotAcknowledged() {
+    setUpTestStream();
+
+    String groupName = "test_group";
+
+    // Add initial entries and create consumer group
+    Map<String, String> entry1 = singletonMap("field1", "value1");
+    jedis.xadd(STREAM_KEY_1, new StreamEntryID("1-0"), entry1);
+    jedis.xgroupCreate(STREAM_KEY_1, groupName, new StreamEntryID("0-0"), true);
+
+    // Read one message to create PEL entry
+    String consumerName = "consumer1";
+    Map<String, StreamEntryID> streamQuery = singletonMap(STREAM_KEY_1,
+      StreamEntryID.XREADGROUP_UNDELIVERED_ENTRY);
+    jedis.xreadGroup(groupName, consumerName, XReadGroupParams.xReadGroupParams().count(1),
+      streamQuery);
+
+    // Add a new entry that was never delivered to any consumer
+    Map<String, String> entry2 = singletonMap("field4", "value4");
+    StreamEntryID id2 = jedis.xadd(STREAM_KEY_1, new StreamEntryID("2-0"), entry2);
+
+    // Verify initial state
+    StreamPendingSummary pending = jedis.xpending(STREAM_KEY_1, groupName);
+    assertEquals(1L, pending.getTotal()); // Only id1 is in PEL
+
+    StreamInfo info = jedis.xinfoStream(STREAM_KEY_1);
+    assertEquals(2L, info.getLength()); // Stream has 2 entries
+
+    // Test XDELEX with ACKNOWLEDGED policy on entry that was never delivered
+    // This should return NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED since id2 was never
+    // delivered to any consumer
+    List<StreamEntryDeletionResult> result = jedis.xdelex(STREAM_KEY_1,
+      StreamDeletionPolicy.ACKNOWLEDGED, id2);
+    assertThat(result, hasSize(1));
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED,
+      result.get(0));
+  }
 }

src/test/java/redis/clients/jedis/resps/StreamEntryDeletionResultTest.java

@@ -10,7 +10,7 @@ public class StreamEntryDeletionResultTest {
   public void testFromCode() {
     assertEquals(StreamEntryDeletionResult.NOT_FOUND, StreamEntryDeletionResult.fromCode(-1));
     assertEquals(StreamEntryDeletionResult.DELETED, StreamEntryDeletionResult.fromCode(1));
-    assertEquals(StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED,
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED,
       StreamEntryDeletionResult.fromCode(2));
   }
 
@@ -25,7 +25,7 @@ public void testFromCodeInvalid() {
   public void testFromLong() {
     assertEquals(StreamEntryDeletionResult.NOT_FOUND, StreamEntryDeletionResult.fromLong(-1L));
     assertEquals(StreamEntryDeletionResult.DELETED, StreamEntryDeletionResult.fromLong(1L));
-    assertEquals(StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED,
+    assertEquals(StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED,
       StreamEntryDeletionResult.fromLong(2L));
   }
 
@@ -38,14 +38,15 @@ public void testFromLongNull() {
   public void testGetCode() {
     assertEquals(-1, StreamEntryDeletionResult.NOT_FOUND.getCode());
     assertEquals(1, StreamEntryDeletionResult.DELETED.getCode());
-    assertEquals(2, StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED.getCode());
+    assertEquals(2,
+      StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED.getCode());
   }
 
   @Test
   public void testToString() {
     assertEquals("NOT_FOUND(-1)", StreamEntryDeletionResult.NOT_FOUND.toString());
     assertEquals("DELETED(1)", StreamEntryDeletionResult.DELETED.toString());
-    assertEquals("ACKNOWLEDGED_NOT_DELETED(2)",
-      StreamEntryDeletionResult.ACKNOWLEDGED_NOT_DELETED.toString());
+    assertEquals("NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED(2)",
+      StreamEntryDeletionResult.NOT_DELETED_UNACKNOWLEDGED_OR_STILL_REFERENCED.toString());
   }
 }