StatelessSession insertAll in batch does not do batching

hibernate-reactive-core/src/main/java/org/hibernate/reactive/session/impl/ReactiveStatelessSessionImpl.java

@@ -150,6 +150,9 @@ private ReactiveStatelessSessionImpl(
 			PersistenceContext persistenceContext) {
 		super( factory, options );
 		this.persistenceContext = persistenceContext;
+		// StatelessSessionImpl constructor sets the Jdbc Batch Size to 0,
+		// setting it to null allows getConfiguredJdbcBatchSize() to return correct configured size
+		setJdbcBatchSize( null );
 		Integer batchSize = getConfiguredJdbcBatchSize();
 		reactiveConnection = batchSize == null || batchSize < 2
 				? connection

hibernate-reactive-core/src/test/java/org/hibernate/reactive/BatchingConnectionTest.java

@@ -145,6 +145,29 @@ public void testBatching(VertxTestContext context) {
 		);
 	}
 
+	@Test
+	public void testBatchingWithStateless(VertxTestContext context) {
+		final GuineaPig[] pigs = {
+				new GuineaPig( 11, "One" ),
+				new GuineaPig( 22, "Two" ),
+				new GuineaPig( 33, "Three" ),
+				new GuineaPig( 44, "Four" ),
+				new GuineaPig( 55, "Five" ),
+				new GuineaPig( 66, "Six" ),
+		};
+		test( context, getMutinySessionFactory()
+				.withStatelessTransaction( s -> s.insertAll( 10, pigs ) )
+				.invoke( () -> {
+					// We expect only one insert query
+					assertThat( sqlTracker.getLoggedQueries() ).hasSize( 1 );
+					// Parameters are different for different dbs, so we cannot do an exact match
+					assertThat( sqlTracker.getLoggedQueries().get( 0 ) )
+							.matches("insert into pig \\(name,version,id\\) values (.*)" );
+					sqlTracker.clear();
+				} )
+		);
+	}
+
 	@Test
 	public void testBatchingConnection(VertxTestContext context) {
 		test( context, openSession()