test: add more tests

src/main/java/momento/lettuce/MomentoRedisReactiveClient.java

@@ -1582,7 +1582,7 @@ public Mono<String> ltrim(K k, long l, long l1) {
     ValidatorUtils.ensureInIntegerRange(l1, "l1");
 
     // When the range is empty, Redis dictates that the list should be deleted.
-    if (l >= 0 && l1 >= 0 && l > l1 || l < 0 && l1 < 0 && l < l1) {
+    if (((l >= 0 && l1 >= 0) || (l < 0 && l1 < 0)) && l > l1) {
       return unlink(k).then(Mono.just(RedisResponse.OK));
     }
 

src/test/java/momento/lettuce/ListTest.java

@@ -135,6 +135,7 @@ public void testLTrimShouldDeleteListOnEmptyRange() {
     var key = randomString();
     var values = generateListOfRandomStrings(10);
 
+    // Positive offsets
     var lPushResponse = client.lpush(key, values.toArray(new String[0])).block();
     assertEquals(10, lPushResponse);
 
@@ -145,6 +146,18 @@ public void testLTrimShouldDeleteListOnEmptyRange() {
     // Verify the list is empty
     var lRangeResponse = client.lrange(key, 0, -1).collectList().block();
     assertEquals(0, lRangeResponse.size());
+
+    // Negative offsets
+    lPushResponse = client.lpush(key, values.toArray(new String[0])).block();
+    assertEquals(10, lPushResponse);
+
+    // Trim on an empty range deletes the list
+    lTrimResponse = client.ltrim(key, -4, -5).block();
+    assertEquals("OK", lTrimResponse);
+
+    // Verify the list is empty
+    lRangeResponse = client.lrange(key, 0, -1).collectList().block();
+    assertEquals(0, lRangeResponse.size());
   }
 
   @Test

src/test/java/momento/lettuce/utils/RangeUtilsTest.java

@@ -0,0 +1,15 @@
+package momento.lettuce.utils;
+
+import io.lettuce.core.ExpireArgs;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class RangeUtilsTest {
+  @Test
+  public void testAdjustEndRangeFromInclusiveToExclusive() {
+    assertEquals(3, RangeUtils.adjustEndRangeFromInclusiveToExclusive(2));
+    assertEquals(null, RangeUtils.adjustEndRangeFromInclusiveToExclusive(-1));
+    assertEquals(-1, RangeUtils.adjustEndRangeFromInclusiveToExclusive(-2));
+  }
+}