Function test_bytesiocopy_writes_to_both

tests/test_stream_lifecycle.py:165–172

``BytesIOCopy`` writes to itself and to ``copy_to``.

()

def test_bytesiocopy_writes_to_both():
    """``BytesIOCopy`` writes to itself and to ``copy_to``."""
    target = io.BytesIO()
    copier = BytesIOCopy(copy_to=target)
    copier.write(b"data")
    copier.flush()
    assert copier.getvalue() == b"data"
    assert target.getvalue() == b"data"


def test_bytesiocopy_flush_propagates():