DATAREDIS-1234 - Consistently return List<Long> from LPOS command.

We now convert pipeline/transaction results to List<Long> to ensure a consistent return type.

Original Pull Request: #570

Author: mp911de

src/main/java/org/springframework/data/redis/connection/lettuce/LettuceListCommands.java

@@ -83,15 +83,17 @@ public List<Long> lPos(byte[] key, byte[] element, @Nullable Integer rank, @Null
 				if (count != null) {
 					pipeline(connection.newLettuceResult(getAsyncConnection().lpos(key, element, count, args)));
 				} else {
-					pipeline(connection.newLettuceResult(getAsyncConnection().lpos(key, element, args)));
+					pipeline(
+							connection.newLettuceResult(getAsyncConnection().lpos(key, element, args), Collections::singletonList));
 				}
 				return null;
 			}
 			if (isQueueing()) {
 				if (count != null) {
 					transaction(connection.newLettuceResult(getAsyncConnection().lpos(key, element, count, args)));
 				} else {
-					transaction(connection.newLettuceResult(getAsyncConnection().lpos(key, element, args)));
+					transaction(
+							connection.newLettuceResult(getAsyncConnection().lpos(key, element, args), Collections::singletonList));
 				}
 				return null;
 			}

src/test/java/org/springframework/data/redis/connection/AbstractConnectionIntegrationTests.java

@@ -1501,9 +1501,9 @@ public void testLPushMultiple() {
 	public void lPos() {
 
 		actual.add(connection.rPush("mylist", "a", "b", "c", "1", "2", "3", "c", "c"));
-		actual.add(connection.lPos("mylist", "c"));
+		actual.add(connection.lPos("mylist", "c", null, null));
 
-		assertThat((Long) getResults().get(1)).isEqualTo(2);
+		assertThat((List<Long>) getResults().get(1)).containsOnly(2L);
 	}
 
 	@Test // DATAREDIS-1196