void () { myFixture.enableInspections(new XmlDefaultAttributeValueInspection()); myFixture.addFileToProject("foo.xsd", """ <schema xmlns="http://www.w3.org/2001/XMLSchema" targetNamespace="def/attr"> <element name="foo"> <complexType> <attribute name="bar" default=""/> </complexType> </element> </schema>"""); myFixture.configureByText("foo.xml", "<foo xmlns=\"def/attr\" bar=/>"); myFixture.doHighlighting(); }