#1206 - Added test cases to reproduce issue

javers-core/src/test/java/org/javers/core/cases/Case1206ArraysNpe.java

@@ -0,0 +1,75 @@
+package org.javers.core.cases;
+
+import org.javers.core.JaversBuilder;
+import org.javers.core.diff.changetype.container.ArrayChange;
+import org.javers.core.diff.changetype.container.ElementValueChange;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.fail;
+
+/**
+ * see https://github.com/javers/javers/issues/1206
+ *
+ * @author Edgars Garsneks
+ */
+public class Case1206ArraysNpe {
+
+    static class BeanWithArray {
+
+        private final String[] items;
+
+        public BeanWithArray(String... items) {
+            this.items = items;
+        }
+
+    }
+
+    @Test
+    public void shouldNotThrowNPEWhenSamplingNullRight() {
+        var a = new BeanWithArray("a");
+        var b = new BeanWithArray(new String[]{null});
+
+        var javers = JaversBuilder.javers().build();
+
+        try {
+            var diff = javers.compare(a, b);
+            var changes = diff.getChanges();
+
+            Assertions.assertEquals(1, changes.size());
+
+            var change = (ArrayChange) changes.get(0);
+            var elementChange = (ElementValueChange) change.getChanges().get(0);
+
+            Assertions.assertEquals(a.items[0], elementChange.getLeftValue());
+            Assertions.assertEquals(b.items[0], elementChange.getRightValue());
+        } catch (Exception e) {
+            fail("Should not throw exception when sampling item.", e);
+        }
+    }
+
+    @Test
+    public void shouldNotThrowNPEWhenSamplingNullLeft() {
+        var a = new BeanWithArray(new String[]{null});
+        var b = new BeanWithArray("a");
+
+        var javers = JaversBuilder.javers().build();
+
+        try {
+            var diff = javers.compare(a, b);
+            var changes = diff.getChanges();
+
+            Assertions.assertEquals(1, changes.size());
+
+            var change = (ArrayChange) changes.get(0);
+            var elementChange = (ElementValueChange) change.getChanges().get(0);
+
+            Assertions.assertEquals(a.items[0], elementChange.getLeftValue());
+            Assertions.assertEquals(b.items[0], elementChange.getRightValue());
+        } catch (Exception e) {
+            fail("Should not throw exception when sampling item.", e);
+        }
+    }
+
+
+}