import pytest class AbstractPipeTests: def test_pipe_exclusive(self, fs, fs_target): fs.pipe_file(fs_target, b"data") assert fs.cat_file(fs_target) == b"data" with pytest.raises(FileExistsError): fs.pipe_file(fs_target, b"data", mode="create") fs.pipe_file(fs_target, b"new data", mode="overwrite") assert fs.cat_file(fs_target) == b"new data"