testFile('settings.gradle') << 'include \'a\', \'b\''
        testFile('external.gradle') << 'ext.appliedScript = this'
        testFile('build.gradle') << '''
allprojects {
   apply from: "$rootDir/external.gradle"
}
subprojects {
    assert appliedScript.class == rootProject.appliedScript.class
}
task doStuff
'''
        inTestDirectory().withTasks('doStuff').run()
    }