diff --git a/teavm-core/src/main/java/org/teavm/tooling/TeaVMTestTool.java b/teavm-core/src/main/java/org/teavm/tooling/TeaVMTestTool.java
index 1d8f225e0..dbeb1fae7 100644
--- a/teavm-core/src/main/java/org/teavm/tooling/TeaVMTestTool.java
+++ b/teavm-core/src/main/java/org/teavm/tooling/TeaVMTestTool.java
@@ -370,7 +370,7 @@ public class TeaVMTestTool {
                 innerWriter.append("\n");
                 innerWriter.append("\nJUnitClient.run();");
                 if (sourceMapsGenerated) {
-                    String sourceMapsFileName = targetName + ".map";
+                    String sourceMapsFileName = targetName.substring(targetName.lastIndexOf('/') + 1) + ".map";
                     innerWriter.append("\n//# sourceMappingURL=").append(sourceMapsFileName);
                 }
             } else {
diff --git a/teavm-html4j/pom.xml b/teavm-html4j/pom.xml
index cbbf55eae..bf777cb34 100644
--- a/teavm-html4j/pom.xml
+++ b/teavm-html4j/pom.xml
@@ -100,6 +100,7 @@
               </transformers>
               <debugInformationGenerated>true</debugInformationGenerated>
               <sourceMapsGenerated>true</sourceMapsGenerated>
+              <sourceFilesCopied>true</sourceFilesCopied>
             </configuration>
           </execution>
         </executions>
diff --git a/teavm-html4j/src/test/java/org/teavm/html4j/test/KnockoutFXTest.java b/teavm-html4j/src/test/java/org/teavm/html4j/test/KnockoutFXTest.java
index e9a7fedfc..11b29035e 100644
--- a/teavm-html4j/src/test/java/org/teavm/html4j/test/KnockoutFXTest.java
+++ b/teavm-html4j/src/test/java/org/teavm/html4j/test/KnockoutFXTest.java
@@ -164,10 +164,12 @@ public final class KnockoutFXTest extends KnockoutTCK implements Transfer {
 
     @Override
     public void loadJSON(JSONCall call) {
+        if (call.isJSONP()) {
+            throw new IllegalArgumentException("This mock does not support JSONP calls");
+        }
         String url = call.composeURL(null);
         String data = urlMap.get(url);
         if (data != null) {
-            data = "[" + data + "]";
             try {
                 call.notifySuccess(toJSON(new ByteArrayInputStream(data.getBytes())));
             } catch (IOException e) {