Map<String, BuildFixture> builds = [:]

        RootBuild(TestFile rootDirectory) {
            super('root', rootDirectory)
        }

        BuildFixture includedBuild(String name) {
            return builds.get(name, new BuildFixture(name, buildDir.file(name)))
        }

        TaskFixture task(String name) {
            return subproject(':').task(name)
        }

        void writeFiles() {