Index: trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java	(revision 9797)
+++ trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java	(revision 9797)
@@ -0,0 +1,28 @@
+// License: GPL. For details, see LICENSE file.
+package org.openstreetmap.josm.io;
+
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+
+import org.junit.Test;
+import org.openstreetmap.josm.Main;
+import org.openstreetmap.josm.TestUtils;
+
+/**
+ * Unit tests of {@link NoteImporter} class.
+ */
+public class NoteImporterTest {
+
+    /**
+     * Non-regression test for <a href="https://josm.openstreetmap.de/ticket/12531">Bug #12531</a>.
+     * @throws Exception if any error occurs
+     */
+    @Test
+    public void testTicket12531() throws Exception {
+        assertNull(Main.map);
+        assertTrue(new NoteImporter().importDataHandleExceptions(
+                new File(TestUtils.getRegressionDataFile(12531, "notes.osn")), null));
+    }
+}