### Question:
CodeGeneratorHelper { public void registerCustomElements() { HtmlSeLionElementSet.getInstance().addAll(config.htmlCustomElements); IOSSeLionElementSet.getInstance().addAll(config.iosCustomElements); AndroidSeLionElementSet.getInstance().addAll(config.androidCustomElements); MobileSeLionElementSet.getInstance().addAll(config.mobileCustomElements); } protected  CodeGeneratorHelper(CodeGeneratorConfig config); void processFiles(); void displayProjectInformation(); void registerCustomElements(); void createSeLionPageDetailsFile();  }### Answer:
@Test public void testRegisterCustomElements() { CodeGeneratorConfig config = new CodeGeneratorConfig(); String[] args = { "-androidCustomElements", "foo.android.A,foo.android.B", "-iosCustomElements", "foo.ios.A,foo.ios.B", "-htmlCustomElements", "foo.html.A,foo.html.B", "-mobileCustomElements", "foo.mobile.A,foo.mobile.B" }; new JCommander(config).parse(args); CodeGeneratorHelper helper = new CodeGeneratorHelper(config); helper.registerCustomElements(); assertTrue(AndroidSeLionElementSet.getInstance().containsAll( Arrays.asList( new SeLionElement("foo.android.A"), new SeLionElement("foo.android.B") ))); assertTrue(IOSSeLionElementSet.getInstance().containsAll( Arrays.asList( new SeLionElement("foo.ios.A"), new SeLionElement("foo.ios.B") ))); assertTrue(HtmlSeLionElementSet.getInstance().containsAll( Arrays.asList( new SeLionElement("foo.html.A"), new SeLionElement("foo.html.B") ))); assertTrue(MobileSeLionElementSet.getInstance().containsAll( Arrays.asList( new SeLionElement("foo.mobile.A"), new SeLionElement("foo.mobile.B") ))); }