def test_with_custom_output(self):
        """build() method can write to a custom file object."""
        from webassets.six import StringIO
        buffer = StringIO()
        self.mkbundle('in1', 'in2', output='out').build(output=buffer)
        assert buffer.getvalue() == 'A\nB'
        assert not self.exists('out')    # file was not written.
dataset/ETHPy150Open miracle2k/webassets/tests/test_bundle_build.py/TestBuildVarious.test_with_custom_output/original