Index: trunk/test/functional/org/openstreetmap/josm/io/MultiFetchServerObjectReaderTest.java
===================================================================
--- trunk/test/functional/org/openstreetmap/josm/io/MultiFetchServerObjectReaderTest.java	(revision 15426)
+++ trunk/test/functional/org/openstreetmap/josm/io/MultiFetchServerObjectReaderTest.java	(revision 15717)
@@ -18,6 +18,8 @@
 import java.text.MessageFormat;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Locale;
 import java.util.Random;
+import java.util.TreeSet;
 import java.util.logging.Logger;
 
@@ -35,4 +37,5 @@
 import org.openstreetmap.josm.data.osm.Node;
 import org.openstreetmap.josm.data.osm.OsmPrimitive;
+import org.openstreetmap.josm.data.osm.OsmPrimitiveType;
 import org.openstreetmap.josm.data.osm.Relation;
 import org.openstreetmap.josm.data.osm.RelationMember;
@@ -42,4 +45,5 @@
 
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import org.openstreetmap.josm.testutils.JOSMTestRules;
 
 /**
@@ -49,4 +53,11 @@
 public class MultiFetchServerObjectReaderTest {
     private static Logger logger = Logger.getLogger(MultiFetchServerObjectReader.class.getName());
+
+    /**
+     * Setup test.
+     */
+    @Rule
+    @SuppressFBWarnings(value = "URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD")
+    public JOSMTestRules test = new JOSMTestRules().preferences();
 
     /**
@@ -332,3 +343,13 @@
         assertEquals(9999999, reader.getMissingPrimitives().iterator().next().getUniqueId());
     }
+
+    /**
+     * Test {@link MultiFetchServerObjectReader#buildRequestString}
+     */
+    @Test
+    public void testBuildRequestString() {
+        String requestString = new MultiFetchServerObjectReader()
+                .buildRequestString(OsmPrimitiveType.WAY, new TreeSet<>(Arrays.asList(130L, 123L, 126L)));
+        assertEquals("ways?ways=123,126,130", requestString);
+    }
 }