Don't merge collection property default value with graph value

CHANGES.txt

@@ -6,6 +6,7 @@ o Update Neo4j to version 3.2.3 in 3.2 profile
 o Update Neo4j to version 3.3.0-alpha05 in 3.3 profile
 o Update java driver version to 1.4.3
 o Test against java driver 1.5-alpha1 in driver-1.5 profile
+o Don't merge collection property default value with graph value
 
 3.0.0-RC1
 o Add verifyConnection configuration property for bolt and http driver

core/src/main/java/org/neo4j/ogm/context/GraphEntityMapper.java

@@ -255,13 +255,12 @@ private void writeProperty(ClassInfo classInfo, Object instance, Property<?, ?>
             if (writer.type().isArray() || Iterable.class.isAssignableFrom(writer.type())) {
                 FieldInfo reader = classInfo.getFieldInfo(property.getKey().toString());
                 if (reader != null) {
-                    Object currentValue = reader.readProperty(instance);
                     Class<?> paramType = writer.type();
                     Class elementType = underlyingElementType(classInfo, property.getKey().toString());
                     if (paramType.isArray()) {
-                        value = EntityAccessManager.merge(paramType, value, (Object[]) currentValue, elementType);
+                        value = EntityAccessManager.merge(paramType, value, new Object[]{} , elementType);
                     } else {
-                        value = EntityAccessManager.merge(paramType, value, (Collection) currentValue, elementType);
+                        value = EntityAccessManager.merge(paramType, value, Collections.emptyList(), elementType);
                     }
                 }
             }

test/src/test/java/org/neo4j/ogm/persistence/examples/numbers/Bucket.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2002-2017 "Neo Technology,"
+ * Network Engine for Objects in Lund AB [http://neotechnology.com]
+ *
+ * This product is licensed to you under the Apache License, Version 2.0 (the "License").
+ * You may not use this product except in compliance with the License.
+ *
+ * This product may include a number of subcomponents with
+ * separate copyright notices and license terms. Your use of the source
+ * code for these subcomponents is subject to the terms and
+ *  conditions of the subcomponent's license, as noted in the LICENSE file.
+ */
+
+package org.neo4j.ogm.persistence.examples.numbers;
+
+import java.util.List;
+
+import org.neo4j.ogm.annotation.NodeEntity;
+
+import static com.google.common.collect.Lists.newArrayList;
+
+/**
+ * @author Frantisek Hartman
+ */
+@NodeEntity
+public class Bucket {
+
+    Long id;
+
+    // collection with default value
+    List<Integer> numbers = newArrayList(1, 2, 3);
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public List<Integer> getNumbers() {
+        return numbers;
+    }
+
+    public void setNumbers(List<Integer> numbers) {
+        this.numbers = numbers;
+    }
+}

test/src/test/java/org/neo4j/ogm/persistence/examples/numbers/BucketIntegrationTest.java

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2002-2017 "Neo Technology,"
+ * Network Engine for Objects in Lund AB [http://neotechnology.com]
+ *
+ * This product is licensed to you under the Apache License, Version 2.0 (the "License").
+ * You may not use this product except in compliance with the License.
+ *
+ * This product may include a number of subcomponents with
+ * separate copyright notices and license terms. Your use of the source
+ * code for these subcomponents is subject to the terms and
+ *  conditions of the subcomponent's license, as noted in the LICENSE file.
+ */
+
+package org.neo4j.ogm.persistence.examples.numbers;
+
+import java.io.IOException;
+
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import org.neo4j.ogm.session.Session;
+import org.neo4j.ogm.session.SessionFactory;
+import org.neo4j.ogm.testutil.MultiDriverTestClass;
+
+import static java.util.Collections.emptyList;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Frantisek Hartman
+ */
+public class BucketIntegrationTest extends MultiDriverTestClass {
+
+    private static SessionFactory sessionFactory;
+
+    private Session session;
+
+    @BeforeClass
+    public static void oneTimeSetUp() {
+        sessionFactory = new SessionFactory(driver, "org.neo4j.ogm.persistence.examples.numbers");
+    }
+
+    @Before
+    public void init() throws IOException {
+        session = sessionFactory.openSession();
+        session.purgeDatabase();
+    }
+
+    @Test
+    public void savedBucketShouldHaveDefaultValue() throws Exception {
+        Bucket bucket = new Bucket();
+        session.save(bucket);
+        session.clear();
+
+        Bucket loaded = session.load(Bucket.class, bucket.getId());
+        assertThat(loaded.getNumbers()).containsOnly(1, 2, 3);
+    }
+
+    @Test
+    public void emptiedBucketShouldBeEmptyAfterReload() throws Exception {
+        Bucket bucket = new Bucket();
+        bucket.setNumbers(emptyList());
+        session.save(bucket);
+        session.clear();
+
+        Bucket loaded = session.load(Bucket.class, bucket.getId());
+        assertThat(loaded.getNumbers()).isEmpty();
+    }
+}