Lines
75.16 %
Functions
71.53 %
Branches
100 %
//! Roundtrip serde Options module.
use alloc::string::String;
use core::fmt;
use serde::{de, ser};
use serde_derive::{Deserialize, Serialize};
use crate::{
de::Deserializer,
error::{Result, SpannedResult},
extensions::Extensions,
ser::{PrettyConfig, Serializer},
};
#[cfg(feature = "std")]
use {
crate::error::{Position, SpannedError},
alloc::vec::Vec,
std::io,
/// Roundtrip serde options.
///
/// # Examples
/// ```
/// use ron::{Options, extensions::Extensions};
/// let ron = Options::default()
/// .with_default_extension(Extensions::IMPLICIT_SOME);
/// let de: Option<i32> = ron.from_str("42").unwrap();
/// let ser = ron.to_string(&de).unwrap();
/// assert_eq!(ser, "42");
#[derive(Clone, Debug, Serialize, Deserialize)] // GRCOV_EXCL_LINE
#[serde(default)]
#[non_exhaustive]
pub struct Options {
/// Extensions that are enabled by default during serialization and
/// deserialization.
/// During serialization, these extensions do NOT have to be explicitly
/// enabled in the parsed RON.
/// During deserialization, these extensions are used, but their explicit
/// activation is NOT included in the output RON.
/// No extensions are enabled by default.
pub default_extensions: Extensions,
/// Default recursion limit that is checked during serialization and
/// If set to `None`, infinite recursion is allowed and stack overflow
/// errors can crash the serialization or deserialization process.
/// Defaults to `Some(128)`, i.e. 128 recursive calls are allowed.
pub recursion_limit: Option<usize>,
}
impl Default for Options {
fn default() -> Self {
Self {
default_extensions: Extensions::empty(),
recursion_limit: Some(128),
impl Options {
#[must_use]
/// Enable `default_extension` by default during serialization and deserialization.
pub fn with_default_extension(mut self, default_extension: Extensions) -> Self {
self.default_extensions |= default_extension;
self
/// Do NOT enable `default_extension` by default during serialization and deserialization.
pub fn without_default_extension(mut self, default_extension: Extensions) -> Self {
self.default_extensions &= !default_extension;
/// Set a maximum recursion limit during serialization and deserialization.
pub fn with_recursion_limit(mut self, recursion_limit: usize) -> Self {
self.recursion_limit = Some(recursion_limit);
/// Disable the recursion limit during serialization and deserialization.
/// If you expect to handle highly recursive datastructures, consider wrapping
/// `ron` with [`serde_stacker`](https://docs.rs/serde_stacker/latest/serde_stacker/).
pub fn without_recursion_limit(mut self) -> Self {
self.recursion_limit = None;
/// A convenience function for building a deserializer
/// and deserializing a value of type `T` from a reader.
pub fn from_reader<R, T>(&self, rdr: R) -> SpannedResult<T>
where
R: io::Read,
T: de::DeserializeOwned,
{
self.from_reader_seed(rdr, core::marker::PhantomData)
/// and deserializing a value of type `T` from a string.
pub fn from_str<'a, T>(&self, s: &'a str) -> SpannedResult<T>
T: de::Deserialize<'a>,
self.from_str_seed(s, core::marker::PhantomData)
/// and deserializing a value of type `T` from bytes.
pub fn from_bytes<'a, T>(&self, s: &'a [u8]) -> SpannedResult<T>
self.from_bytes_seed(s, core::marker::PhantomData)
/// and deserializing a value of type `T` from a reader
/// and a seed.
// FIXME: panic is not actually possible, remove once utf8_chunks is stabilized
#[allow(clippy::missing_panics_doc)]
pub fn from_reader_seed<R, S, T>(&self, mut rdr: R, seed: S) -> SpannedResult<T>
S: for<'a> de::DeserializeSeed<'a, Value = T>,
let mut bytes = Vec::new();
let io_err = if let Err(err) = rdr.read_to_end(&mut bytes) {
err
} else {
return self.from_bytes_seed(&bytes, seed);
// Try to compute a good error position for the I/O error
// FIXME: use [`utf8_chunks`](https://github.com/rust-lang/rust/issues/99543) once stabilised
#[allow(clippy::expect_used)]
let valid_input = match core::str::from_utf8(&bytes) {
Ok(valid_input) => valid_input,
Err(err) => core::str::from_utf8(&bytes[..err.valid_up_to()])
.expect("source is valid up to error"),
Err(SpannedError {
code: io_err.into(),
position: Position::from_src_end(valid_input),
})
/// and deserializing a value of type `T` from a string
pub fn from_str_seed<'a, S, T>(&self, s: &'a str, seed: S) -> SpannedResult<T>
S: de::DeserializeSeed<'a, Value = T>,
let mut deserializer = Deserializer::from_str_with_options(s, self)?;
let value = seed
.deserialize(&mut deserializer)
.map_err(|e| deserializer.span_error(e))?;
deserializer.end().map_err(|e| deserializer.span_error(e))?;
Ok(value)
/// and deserializing a value of type `T` from bytes
pub fn from_bytes_seed<'a, S, T>(&self, s: &'a [u8], seed: S) -> SpannedResult<T>
let mut deserializer = Deserializer::from_bytes_with_options(s, self)?;
/// Serializes `value` into `writer`.
/// This function does not generate any newlines or nice formatting;
/// if you want that, you can use
/// [`to_writer_pretty`][Self::to_writer_pretty] instead.
pub fn to_writer<W, T>(&self, writer: W, value: &T) -> Result<()>
W: fmt::Write,
T: ?Sized + ser::Serialize,
let mut s = Serializer::with_options(writer, None, self)?;
value.serialize(&mut s)
/// Serializes `value` into `writer` in a pretty way.
pub fn to_writer_pretty<W, T>(&self, writer: W, value: &T, config: PrettyConfig) -> Result<()>
let mut s = Serializer::with_options(writer, Some(config), self)?;
/// [`to_io_writer_pretty`][Self::to_io_writer_pretty] instead.
pub fn to_io_writer<W, T>(&self, writer: W, value: &T) -> Result<()>
W: io::Write,
let mut adapter = Adapter {
writer,
error: Ok(()),
let result = self.to_writer(&mut adapter, value);
adapter.error?;
result
pub fn to_io_writer_pretty<W, T>(
&self,
writer: W,
value: &T,
config: PrettyConfig,
) -> Result<()>
let result = self.to_writer_pretty(&mut adapter, value, config);
/// Serializes `value` and returns it as string.
/// [`to_string_pretty`][Self::to_string_pretty] instead.
pub fn to_string<T>(&self, value: &T) -> Result<String>
let mut output = String::new();
let mut s = Serializer::with_options(&mut output, None, self)?;
value.serialize(&mut s)?;
Ok(output)
/// Serializes `value` in the recommended RON layout in a pretty way.
pub fn to_string_pretty<T>(&self, value: &T, config: PrettyConfig) -> Result<String>
let mut s = Serializer::with_options(&mut output, Some(config), self)?;
// Adapter from io::Write to fmt::Write that keeps the error
struct Adapter<W: io::Write> {
error: io::Result<()>,
impl<T: io::Write> fmt::Write for Adapter<T> {
fn write_str(&mut self, s: &str) -> fmt::Result {
match self.writer.write_all(s.as_bytes()) {
Ok(()) => Ok(()),
Err(e) => {
self.error = Err(e);
Err(fmt::Error)