void () { final PsiFile xmlFile = myFixture.addFileToProject("p.xml", """ <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"> <properties> </properties>"""); final PsiFile propFile = myFixture.addFileToProject("p.properties", ""); final PropertiesFile xmlPropFile = PropertiesImplUtil.getPropertiesFile(xmlFile); final PropertiesFile propertiesFile = PropertiesImplUtil.getPropertiesFile(propFile); assertNotNull(xmlPropFile); assertNotNull(propertiesFile); assertEquals(xmlPropFile, assertOneElement(xmlPropFile.getResourceBundle().getPropertiesFiles())); assertEquals(propertiesFile, assertOneElement(propertiesFile.getResourceBundle().getPropertiesFiles())); }