Method readline

crates/stdlib/src/mmap.rs:1152–1177

(&self, vm: &VirtualMachine)

        #[pymethod]
        fn readline(&self, vm: &VirtualMachine) -> PyResult<PyBytesRef> {
            let pos = self.pos();
            let mmap = self.check_valid(vm)?;

            let remaining = self.__len__().saturating_sub(pos);
            if remaining == 0 {
                return Ok(PyBytes::from(vec![]).into_ref(&vm.ctx));
            }

            let slice = mmap.as_ref().unwrap().as_slice();
            let eof = slice[pos..].iter().position(|&x| x == b'\n');

            let end_pos = if let Some(i) = eof {
                pos + i + 1
            } else {
                self.__len__()
            };

            let bytes = slice[pos..end_pos].to_vec();

            let result = PyBytes::from(bytes).into_ref(&vm.ctx);

            self.advance_pos(end_pos - pos);

            Ok(result)
        }

        #[cfg(unix)]
        #[pymethod]