}
        }
        def jar = file('build/test.jar')

        when:
        buildFile.text = jarWithManifest("")
        run 'jar'

        then:
        jar.manifest.mainAttributes.getValue('attr') == null

        when: "Attribute added"
        buildFile.text = jarWithManifest("attributes(attr: 'Hello')")
        run 'jar'

        then:
        executedAndNotSkipped ':jar'