void () { myFixture.configureByFile("web-app_2_5.xsd"); myFixture.configureByText("a.xml", """ <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" <warning descr="Namespace declaration is never used">xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"</warning> xsi:schemaLocation="http://java.sun.com/xml/ns/javaee web-app_2_5.xsd" version="2.5"> </web-app>"""); myFixture.testHighlighting(); }