Method fromfile

crates/stdlib/src/array.rs:867–892

(&self, f: PyObjectRef, n: isize, vm: &VirtualMachine)

        #[pymethod]
        fn fromfile(&self, f: PyObjectRef, n: isize, vm: &VirtualMachine) -> PyResult<()> {
            let itemsize = self.itemsize();
            if n < 0 {
                return Err(vm.new_value_error("negative count"));
            }
            let n = vm.check_repeat_or_overflow_error(itemsize, n)?;
            let n_bytes = n * itemsize;

            let b = vm.call_method(&f, "read", (n_bytes,))?;
            let b = b
                .downcast::<PyBytes>()
                .map_err(|_| vm.new_type_error("read() didn't return bytes"))?;

            let not_enough_bytes = b.len() != n_bytes;

            self._from_bytes(b.as_bytes(), itemsize, vm)?;

            if not_enough_bytes {
                Err(vm.new_exception_msg(
                    vm.ctx.exceptions.eof_error.to_owned(),
                    "read() didn't return enough bytes".into(),
                ))
            } else {
                Ok(())
            }
        }

        #[pymethod]
        fn byteswap(&self) {