def test_empty_bundles(self):
        assert_raises(BuildError, self.mkbundle(output='out').build)
        # Even an empty child bundle structure would not bypass this.
        assert_raises(BuildError, self.mkbundle(self.mkbundle(), output='out').build)
        # However, empty child bundles are perfectly valid per se.
        #There just needs to be *something* to build.
        self.mkbundle(self.mkbundle(), 'in1', output='out').build()
Building an empty bundle must be an error. Creating an
dataset/ETHPy150Open miracle2k/webassets/tests/test_bundle_build.py/TestBuildVarious.test_empty_bundles