diff --git a/testsrc/org/mozilla/javascript/tests/commonjs/module/provider/UrlModuleSourceProviderTest.java b/testsrc/org/mozilla/javascript/tests/commonjs/module/provider/UrlModuleSourceProviderTest.java
index 4924b1afd8..70b8e6c6b1 100644
--- a/testsrc/org/mozilla/javascript/tests/commonjs/module/provider/UrlModuleSourceProviderTest.java
+++ b/testsrc/org/mozilla/javascript/tests/commonjs/module/provider/UrlModuleSourceProviderTest.java
@@ -4,8 +4,11 @@
 
 package org.mozilla.javascript.tests.commonjs.module.provider;
 
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.net.URLConnection;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.attribute.FileTime;
@@ -67,6 +70,15 @@ public void testModuleModified() throws Exception {
         Assert.assertNotEquals("Modified", ModuleSourceProvider.NOT_MODIFIED, result);
     }
 
+    @Test
+    public void getCharacterEncodingCanBeModifiedInSubclass() throws NoSuchMethodException {
+        Method method =
+                UrlModuleSourceProvider.class.getDeclaredMethod(
+                        "getCharacterEncoding", new Class[] {URLConnection.class});
+        int mods = method.getModifiers();
+        Assert.assertTrue(Modifier.isPublic(mods) || Modifier.isProtected(mods));
+    }
+
     private static URI getModuleURI(final Path filePath) throws URISyntaxException {
         final String uriString = filePath.toUri().toASCIIString();
         return new URI(uriString.substring(0, uriString.lastIndexOf('.')));