from os.path import join from io import BufferedReader, BytesIO from numpy.compat import isfileobj from numpy.testing import assert_ from numpy.testing import tempdir def test_isfileobj(): with tempdir(prefix="numpy_test_compat_") as folder: filename = join(folder, 'a.bin') with open(filename, 'wb') as f: assert_(isfileobj(f)) with open(filename, 'ab') as f: assert_(isfileobj(f)) with open(filename, 'rb') as f: assert_(isfileobj(f)) assert_(isfileobj(BufferedReader(BytesIO())) is False)