Index: trunk/test/unit/org/openstreetmap/josm/gui/preferences/map/MapPaintPreferenceTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/gui/preferences/map/MapPaintPreferenceTest.java	(revision 8938)
+++ trunk/test/unit/org/openstreetmap/josm/gui/preferences/map/MapPaintPreferenceTest.java	(revision 8940)
@@ -6,6 +6,7 @@
 
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
 
 import org.junit.BeforeClass;
@@ -39,12 +40,14 @@
                 .loadAndGetAvailableSources();
         assertFalse(sources.isEmpty());
-        Collection<Throwable> allErrors = new ArrayList<>();
+        Map<String, Collection<Throwable>> allErrors = new HashMap<>();
         for (ExtendedSourceEntry source : sources) {
             System.out.print(source.url);
             Collection<Throwable> errors = MapPaintStyles.addStyle(source);
             System.out.println(errors.isEmpty() ? " => OK" : " => KO");
-            allErrors.addAll(errors);
+            if (!errors.isEmpty()) {
+                allErrors.put(source.url, errors);
+            }
         }
-        assertTrue(allErrors.isEmpty());
+        assertTrue(allErrors.toString(), allErrors.isEmpty());
     }
 }