Revision control
Copy as Markdown
Other Tools
//! Serialize a Rust data structure into JSON data.
use crate::error::{Error, ErrorCode, Result};
use crate::io;
use alloc::string::{String, ToString};
use alloc::vec::Vec;
use core::fmt::{self, Display};
use core::num::FpCategory;
use serde::ser::{self, Impossible, Serialize};
/// A structure for serializing Rust values into JSON.
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
pub struct Serializer<W, F = CompactFormatter> {
writer: W,
formatter: F,
}
impl<W> Serializer<W>
where
W: io::Write,
{
/// Creates a new JSON serializer.
#[inline]
pub fn new(writer: W) -> Self {
Serializer::with_formatter(writer, CompactFormatter)
}
}
impl<'a, W> Serializer<W, PrettyFormatter<'a>>
where
W: io::Write,
{
/// Creates a new JSON pretty print serializer.
#[inline]
pub fn pretty(writer: W) -> Self {
Serializer::with_formatter(writer, PrettyFormatter::new())
}
}
impl<W, F> Serializer<W, F>
where
W: io::Write,
F: Formatter,
{
/// Creates a new JSON visitor whose output will be written to the writer
/// specified.
#[inline]
pub fn with_formatter(writer: W, formatter: F) -> Self {
Serializer { writer, formatter }
}
/// Unwrap the `Writer` from the `Serializer`.
#[inline]
pub fn into_inner(self) -> W {
self.writer
}
}
impl<'a, W, F> ser::Serializer for &'a mut Serializer<W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
type SerializeSeq = Compound<'a, W, F>;
type SerializeTuple = Compound<'a, W, F>;
type SerializeTupleStruct = Compound<'a, W, F>;
type SerializeTupleVariant = Compound<'a, W, F>;
type SerializeMap = Compound<'a, W, F>;
type SerializeStruct = Compound<'a, W, F>;
type SerializeStructVariant = Compound<'a, W, F>;
#[inline]
fn serialize_bool(self, value: bool) -> Result<()> {
self.formatter
.write_bool(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_i8(self, value: i8) -> Result<()> {
self.formatter
.write_i8(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_i16(self, value: i16) -> Result<()> {
self.formatter
.write_i16(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_i32(self, value: i32) -> Result<()> {
self.formatter
.write_i32(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_i64(self, value: i64) -> Result<()> {
self.formatter
.write_i64(&mut self.writer, value)
.map_err(Error::io)
}
fn serialize_i128(self, value: i128) -> Result<()> {
self.formatter
.write_i128(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_u8(self, value: u8) -> Result<()> {
self.formatter
.write_u8(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_u16(self, value: u16) -> Result<()> {
self.formatter
.write_u16(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_u32(self, value: u32) -> Result<()> {
self.formatter
.write_u32(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_u64(self, value: u64) -> Result<()> {
self.formatter
.write_u64(&mut self.writer, value)
.map_err(Error::io)
}
fn serialize_u128(self, value: u128) -> Result<()> {
self.formatter
.write_u128(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_f32(self, value: f32) -> Result<()> {
match value.classify() {
FpCategory::Nan | FpCategory::Infinite => self
.formatter
.write_null(&mut self.writer)
.map_err(Error::io),
_ => self
.formatter
.write_f32(&mut self.writer, value)
.map_err(Error::io),
}
}
#[inline]
fn serialize_f64(self, value: f64) -> Result<()> {
match value.classify() {
FpCategory::Nan | FpCategory::Infinite => self
.formatter
.write_null(&mut self.writer)
.map_err(Error::io),
_ => self
.formatter
.write_f64(&mut self.writer, value)
.map_err(Error::io),
}
}
#[inline]
fn serialize_char(self, value: char) -> Result<()> {
// A char encoded as UTF-8 takes 4 bytes at most.
let mut buf = [0; 4];
self.serialize_str(value.encode_utf8(&mut buf))
}
#[inline]
fn serialize_str(self, value: &str) -> Result<()> {
format_escaped_str(&mut self.writer, &mut self.formatter, value).map_err(Error::io)
}
#[inline]
fn serialize_bytes(self, value: &[u8]) -> Result<()> {
self.formatter
.write_byte_array(&mut self.writer, value)
.map_err(Error::io)
}
#[inline]
fn serialize_unit(self) -> Result<()> {
self.formatter
.write_null(&mut self.writer)
.map_err(Error::io)
}
#[inline]
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
self.serialize_unit()
}
#[inline]
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
) -> Result<()> {
self.serialize_str(variant)
}
/// Serialize newtypes without an object wrapper.
#[inline]
fn serialize_newtype_struct<T>(self, _name: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
#[inline]
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
value: &T,
) -> Result<()>
where
T: ?Sized + Serialize,
{
tri!(self
.formatter
.begin_object(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_key(&mut self.writer, true)
.map_err(Error::io));
tri!(self.serialize_str(variant));
tri!(self
.formatter
.end_object_key(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_value(&mut self.writer)
.map_err(Error::io));
tri!(value.serialize(&mut *self));
tri!(self
.formatter
.end_object_value(&mut self.writer)
.map_err(Error::io));
self.formatter
.end_object(&mut self.writer)
.map_err(Error::io)
}
#[inline]
fn serialize_none(self) -> Result<()> {
self.serialize_unit()
}
#[inline]
fn serialize_some<T>(self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
#[inline]
fn serialize_seq(self, len: Option<usize>) -> Result<Self::SerializeSeq> {
tri!(self
.formatter
.begin_array(&mut self.writer)
.map_err(Error::io));
if len == Some(0) {
tri!(self
.formatter
.end_array(&mut self.writer)
.map_err(Error::io));
Ok(Compound::Map {
ser: self,
state: State::Empty,
})
} else {
Ok(Compound::Map {
ser: self,
state: State::First,
})
}
}
#[inline]
fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple> {
self.serialize_seq(Some(len))
}
#[inline]
fn serialize_tuple_struct(
self,
_name: &'static str,
len: usize,
) -> Result<Self::SerializeTupleStruct> {
self.serialize_seq(Some(len))
}
#[inline]
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
len: usize,
) -> Result<Self::SerializeTupleVariant> {
tri!(self
.formatter
.begin_object(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_key(&mut self.writer, true)
.map_err(Error::io));
tri!(self.serialize_str(variant));
tri!(self
.formatter
.end_object_key(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_value(&mut self.writer)
.map_err(Error::io));
self.serialize_seq(Some(len))
}
#[inline]
fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap> {
tri!(self
.formatter
.begin_object(&mut self.writer)
.map_err(Error::io));
if len == Some(0) {
tri!(self
.formatter
.end_object(&mut self.writer)
.map_err(Error::io));
Ok(Compound::Map {
ser: self,
state: State::Empty,
})
} else {
Ok(Compound::Map {
ser: self,
state: State::First,
})
}
}
#[inline]
fn serialize_struct(self, name: &'static str, len: usize) -> Result<Self::SerializeStruct> {
match name {
#[cfg(feature = "arbitrary_precision")]
crate::number::TOKEN => Ok(Compound::Number { ser: self }),
#[cfg(feature = "raw_value")]
crate::raw::TOKEN => Ok(Compound::RawValue { ser: self }),
_ => self.serialize_map(Some(len)),
}
}
#[inline]
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
len: usize,
) -> Result<Self::SerializeStructVariant> {
tri!(self
.formatter
.begin_object(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_key(&mut self.writer, true)
.map_err(Error::io));
tri!(self.serialize_str(variant));
tri!(self
.formatter
.end_object_key(&mut self.writer)
.map_err(Error::io));
tri!(self
.formatter
.begin_object_value(&mut self.writer)
.map_err(Error::io));
self.serialize_map(Some(len))
}
fn collect_str<T>(self, value: &T) -> Result<()>
where
T: ?Sized + Display,
{
use self::fmt::Write;
struct Adapter<'ser, W: 'ser, F: 'ser> {
writer: &'ser mut W,
formatter: &'ser mut F,
error: Option<io::Error>,
}
impl<'ser, W, F> Write for Adapter<'ser, W, F>
where
W: io::Write,
F: Formatter,
{
fn write_str(&mut self, s: &str) -> fmt::Result {
debug_assert!(self.error.is_none());
match format_escaped_str_contents(self.writer, self.formatter, s) {
Ok(()) => Ok(()),
Err(err) => {
self.error = Some(err);
Err(fmt::Error)
}
}
}
}
tri!(self
.formatter
.begin_string(&mut self.writer)
.map_err(Error::io));
let mut adapter = Adapter {
writer: &mut self.writer,
formatter: &mut self.formatter,
error: None,
};
match write!(adapter, "{}", value) {
Ok(()) => debug_assert!(adapter.error.is_none()),
Err(fmt::Error) => {
return Err(Error::io(adapter.error.expect("there should be an error")));
}
}
self.formatter
.end_string(&mut self.writer)
.map_err(Error::io)
}
}
// Not public API. Should be pub(crate).
#[doc(hidden)]
#[derive(Eq, PartialEq)]
pub enum State {
Empty,
First,
Rest,
}
// Not public API. Should be pub(crate).
#[doc(hidden)]
pub enum Compound<'a, W: 'a, F: 'a> {
Map {
ser: &'a mut Serializer<W, F>,
state: State,
},
#[cfg(feature = "arbitrary_precision")]
Number { ser: &'a mut Serializer<W, F> },
#[cfg(feature = "raw_value")]
RawValue { ser: &'a mut Serializer<W, F> },
}
impl<'a, W, F> ser::SerializeSeq for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_element<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
match self {
Compound::Map { ser, state } => {
tri!(ser
.formatter
.begin_array_value(&mut ser.writer, *state == State::First)
.map_err(Error::io));
*state = State::Rest;
tri!(value.serialize(&mut **ser));
ser.formatter
.end_array_value(&mut ser.writer)
.map_err(Error::io)
}
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
#[inline]
fn end(self) -> Result<()> {
match self {
Compound::Map { ser, state } => match state {
State::Empty => Ok(()),
_ => ser.formatter.end_array(&mut ser.writer).map_err(Error::io),
},
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
}
impl<'a, W, F> ser::SerializeTuple for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_element<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
#[inline]
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
}
impl<'a, W, F> ser::SerializeTupleStruct for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_field<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
#[inline]
fn end(self) -> Result<()> {
ser::SerializeSeq::end(self)
}
}
impl<'a, W, F> ser::SerializeTupleVariant for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_field<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
ser::SerializeSeq::serialize_element(self, value)
}
#[inline]
fn end(self) -> Result<()> {
match self {
Compound::Map { ser, state } => {
match state {
State::Empty => {}
_ => tri!(ser.formatter.end_array(&mut ser.writer).map_err(Error::io)),
}
tri!(ser
.formatter
.end_object_value(&mut ser.writer)
.map_err(Error::io));
ser.formatter.end_object(&mut ser.writer).map_err(Error::io)
}
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
}
impl<'a, W, F> ser::SerializeMap for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_key<T>(&mut self, key: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
match self {
Compound::Map { ser, state } => {
tri!(ser
.formatter
.begin_object_key(&mut ser.writer, *state == State::First)
.map_err(Error::io));
*state = State::Rest;
tri!(key.serialize(MapKeySerializer { ser: *ser }));
ser.formatter
.end_object_key(&mut ser.writer)
.map_err(Error::io)
}
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
#[inline]
fn serialize_value<T>(&mut self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
match self {
Compound::Map { ser, .. } => {
tri!(ser
.formatter
.begin_object_value(&mut ser.writer)
.map_err(Error::io));
tri!(value.serialize(&mut **ser));
ser.formatter
.end_object_value(&mut ser.writer)
.map_err(Error::io)
}
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
#[inline]
fn end(self) -> Result<()> {
match self {
Compound::Map { ser, state } => match state {
State::Empty => Ok(()),
_ => ser.formatter.end_object(&mut ser.writer).map_err(Error::io),
},
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
}
impl<'a, W, F> ser::SerializeStruct for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
match self {
Compound::Map { .. } => ser::SerializeMap::serialize_entry(self, key, value),
#[cfg(feature = "arbitrary_precision")]
Compound::Number { ser, .. } => {
if key == crate::number::TOKEN {
value.serialize(NumberStrEmitter(ser))
} else {
Err(invalid_number())
}
}
#[cfg(feature = "raw_value")]
Compound::RawValue { ser, .. } => {
if key == crate::raw::TOKEN {
value.serialize(RawValueStrEmitter(ser))
} else {
Err(invalid_raw_value())
}
}
}
}
#[inline]
fn end(self) -> Result<()> {
match self {
Compound::Map { .. } => ser::SerializeMap::end(self),
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => Ok(()),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => Ok(()),
}
}
}
impl<'a, W, F> ser::SerializeStructVariant for Compound<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
match *self {
Compound::Map { .. } => ser::SerializeStruct::serialize_field(self, key, value),
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
#[inline]
fn end(self) -> Result<()> {
match self {
Compound::Map { ser, state } => {
match state {
State::Empty => {}
_ => tri!(ser.formatter.end_object(&mut ser.writer).map_err(Error::io)),
}
tri!(ser
.formatter
.end_object_value(&mut ser.writer)
.map_err(Error::io));
ser.formatter.end_object(&mut ser.writer).map_err(Error::io)
}
#[cfg(feature = "arbitrary_precision")]
Compound::Number { .. } => unreachable!(),
#[cfg(feature = "raw_value")]
Compound::RawValue { .. } => unreachable!(),
}
}
}
struct MapKeySerializer<'a, W: 'a, F: 'a> {
ser: &'a mut Serializer<W, F>,
}
#[cfg(feature = "arbitrary_precision")]
fn invalid_number() -> Error {
Error::syntax(ErrorCode::InvalidNumber, 0, 0)
}
#[cfg(feature = "raw_value")]
fn invalid_raw_value() -> Error {
Error::syntax(ErrorCode::ExpectedSomeValue, 0, 0)
}
fn key_must_be_a_string() -> Error {
Error::syntax(ErrorCode::KeyMustBeAString, 0, 0)
}
fn float_key_must_be_finite() -> Error {
Error::syntax(ErrorCode::FloatKeyMustBeFinite, 0, 0)
}
impl<'a, W, F> ser::Serializer for MapKeySerializer<'a, W, F>
where
W: io::Write,
F: Formatter,
{
type Ok = ();
type Error = Error;
#[inline]
fn serialize_str(self, value: &str) -> Result<()> {
self.ser.serialize_str(value)
}
#[inline]
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
variant: &'static str,
) -> Result<()> {
self.ser.serialize_str(variant)
}
#[inline]
fn serialize_newtype_struct<T>(self, _name: &'static str, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
type SerializeSeq = Impossible<(), Error>;
type SerializeTuple = Impossible<(), Error>;
type SerializeTupleStruct = Impossible<(), Error>;
type SerializeTupleVariant = Impossible<(), Error>;
type SerializeMap = Impossible<(), Error>;
type SerializeStruct = Impossible<(), Error>;
type SerializeStructVariant = Impossible<(), Error>;
fn serialize_bool(self, value: bool) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_bool(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_i8(self, value: i8) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_i8(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_i16(self, value: i16) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_i16(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_i32(self, value: i32) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_i32(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_i64(self, value: i64) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_i64(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_i128(self, value: i128) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_i128(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_u8(self, value: u8) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_u8(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_u16(self, value: u16) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_u16(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_u32(self, value: u32) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_u32(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_u64(self, value: u64) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_u64(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_u128(self, value: u128) -> Result<()> {
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_u128(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_f32(self, value: f32) -> Result<()> {
if !value.is_finite() {
return Err(float_key_must_be_finite());
}
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_f32(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_f64(self, value: f64) -> Result<()> {
if !value.is_finite() {
return Err(float_key_must_be_finite());
}
tri!(self
.ser
.formatter
.begin_string(&mut self.ser.writer)
.map_err(Error::io));
tri!(self
.ser
.formatter
.write_f64(&mut self.ser.writer, value)
.map_err(Error::io));
self.ser
.formatter
.end_string(&mut self.ser.writer)
.map_err(Error::io)
}
fn serialize_char(self, value: char) -> Result<()> {
self.ser.serialize_str(&value.to_string())
}
fn serialize_bytes(self, _value: &[u8]) -> Result<()> {
Err(key_must_be_a_string())
}
fn serialize_unit(self) -> Result<()> {
Err(key_must_be_a_string())
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
Err(key_must_be_a_string())
}
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T,
) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(key_must_be_a_string())
}
fn serialize_none(self) -> Result<()> {
Err(key_must_be_a_string())
}
fn serialize_some<T>(self, value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
value.serialize(self)
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
Err(key_must_be_a_string())
}
fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple> {
Err(key_must_be_a_string())
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct> {
Err(key_must_be_a_string())
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant> {
Err(key_must_be_a_string())
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap> {
Err(key_must_be_a_string())
}
fn serialize_struct(self, _name: &'static str, _len: usize) -> Result<Self::SerializeStruct> {
Err(key_must_be_a_string())
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant> {
Err(key_must_be_a_string())
}
fn collect_str<T>(self, value: &T) -> Result<()>
where
T: ?Sized + Display,
{
self.ser.collect_str(value)
}
}
#[cfg(feature = "arbitrary_precision")]
struct NumberStrEmitter<'a, W: 'a + io::Write, F: 'a + Formatter>(&'a mut Serializer<W, F>);
#[cfg(feature = "arbitrary_precision")]
impl<'a, W: io::Write, F: Formatter> ser::Serializer for NumberStrEmitter<'a, W, F> {
type Ok = ();
type Error = Error;
type SerializeSeq = Impossible<(), Error>;
type SerializeTuple = Impossible<(), Error>;
type SerializeTupleStruct = Impossible<(), Error>;
type SerializeTupleVariant = Impossible<(), Error>;
type SerializeMap = Impossible<(), Error>;
type SerializeStruct = Impossible<(), Error>;
type SerializeStructVariant = Impossible<(), Error>;
fn serialize_bool(self, _v: bool) -> Result<()> {
Err(invalid_number())
}
fn serialize_i8(self, _v: i8) -> Result<()> {
Err(invalid_number())
}
fn serialize_i16(self, _v: i16) -> Result<()> {
Err(invalid_number())
}
fn serialize_i32(self, _v: i32) -> Result<()> {
Err(invalid_number())
}
fn serialize_i64(self, _v: i64) -> Result<()> {
Err(invalid_number())
}
fn serialize_i128(self, _v: i128) -> Result<()> {
Err(invalid_number())
}
fn serialize_u8(self, _v: u8) -> Result<()> {
Err(invalid_number())
}
fn serialize_u16(self, _v: u16) -> Result<()> {
Err(invalid_number())
}
fn serialize_u32(self, _v: u32) -> Result<()> {
Err(invalid_number())
}
fn serialize_u64(self, _v: u64) -> Result<()> {
Err(invalid_number())
}
fn serialize_u128(self, _v: u128) -> Result<()> {
Err(invalid_number())
}
fn serialize_f32(self, _v: f32) -> Result<()> {
Err(invalid_number())
}
fn serialize_f64(self, _v: f64) -> Result<()> {
Err(invalid_number())
}
fn serialize_char(self, _v: char) -> Result<()> {
Err(invalid_number())
}
fn serialize_str(self, value: &str) -> Result<()> {
let NumberStrEmitter(serializer) = self;
serializer
.formatter
.write_number_str(&mut serializer.writer, value)
.map_err(Error::io)
}
fn serialize_bytes(self, _value: &[u8]) -> Result<()> {
Err(invalid_number())
}
fn serialize_none(self) -> Result<()> {
Err(invalid_number())
}
fn serialize_some<T>(self, _value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(invalid_number())
}
fn serialize_unit(self) -> Result<()> {
Err(invalid_number())
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
Err(invalid_number())
}
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
) -> Result<()> {
Err(invalid_number())
}
fn serialize_newtype_struct<T>(self, _name: &'static str, _value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(invalid_number())
}
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T,
) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(invalid_number())
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
Err(invalid_number())
}
fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple> {
Err(invalid_number())
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct> {
Err(invalid_number())
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant> {
Err(invalid_number())
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap> {
Err(invalid_number())
}
fn serialize_struct(self, _name: &'static str, _len: usize) -> Result<Self::SerializeStruct> {
Err(invalid_number())
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant> {
Err(invalid_number())
}
}
#[cfg(feature = "raw_value")]
struct RawValueStrEmitter<'a, W: 'a + io::Write, F: 'a + Formatter>(&'a mut Serializer<W, F>);
#[cfg(feature = "raw_value")]
impl<'a, W: io::Write, F: Formatter> ser::Serializer for RawValueStrEmitter<'a, W, F> {
type Ok = ();
type Error = Error;
type SerializeSeq = Impossible<(), Error>;
type SerializeTuple = Impossible<(), Error>;
type SerializeTupleStruct = Impossible<(), Error>;
type SerializeTupleVariant = Impossible<(), Error>;
type SerializeMap = Impossible<(), Error>;
type SerializeStruct = Impossible<(), Error>;
type SerializeStructVariant = Impossible<(), Error>;
fn serialize_bool(self, _v: bool) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_i8(self, _v: i8) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_i16(self, _v: i16) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_i32(self, _v: i32) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_i64(self, _v: i64) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_i128(self, _v: i128) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_u8(self, _v: u8) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_u16(self, _v: u16) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_u32(self, _v: u32) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_u64(self, _v: u64) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_u128(self, _v: u128) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_f32(self, _v: f32) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_f64(self, _v: f64) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_char(self, _v: char) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_str(self, value: &str) -> Result<()> {
let RawValueStrEmitter(serializer) = self;
serializer
.formatter
.write_raw_fragment(&mut serializer.writer, value)
.map_err(Error::io)
}
fn serialize_bytes(self, _value: &[u8]) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_none(self) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_some<T>(self, _value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_unit(self) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_unit_struct(self, _name: &'static str) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_unit_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
) -> Result<()> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_newtype_struct<T>(self, _name: &'static str, _value: &T) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_newtype_variant<T>(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_value: &T,
) -> Result<()>
where
T: ?Sized + Serialize,
{
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_tuple_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_struct(self, _name: &'static str, _len: usize) -> Result<Self::SerializeStruct> {
Err(ser::Error::custom("expected RawValue"))
}
fn serialize_struct_variant(
self,
_name: &'static str,
_variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant> {
Err(ser::Error::custom("expected RawValue"))
}
fn collect_str<T>(self, value: &T) -> Result<Self::Ok>
where
T: ?Sized + Display,
{
self.serialize_str(&value.to_string())
}
}
/// Represents a character escape code in a type-safe manner.
pub enum CharEscape {
/// An escaped quote `"`
Quote,
/// An escaped reverse solidus `\`
ReverseSolidus,
/// An escaped solidus `/`
Solidus,
/// An escaped backspace character (usually escaped as `\b`)
Backspace,
/// An escaped form feed character (usually escaped as `\f`)
FormFeed,
/// An escaped line feed character (usually escaped as `\n`)
LineFeed,
/// An escaped carriage return character (usually escaped as `\r`)
CarriageReturn,
/// An escaped tab character (usually escaped as `\t`)
Tab,
/// An escaped ASCII plane control character (usually escaped as
/// `\u00XX` where `XX` are two hex characters)
AsciiControl(u8),
}
impl CharEscape {
#[inline]
fn from_escape_table(escape: u8, byte: u8) -> CharEscape {
match escape {
self::BB => CharEscape::Backspace,
self::TT => CharEscape::Tab,
self::NN => CharEscape::LineFeed,
self::FF => CharEscape::FormFeed,
self::RR => CharEscape::CarriageReturn,
self::QU => CharEscape::Quote,
self::BS => CharEscape::ReverseSolidus,
self::UU => CharEscape::AsciiControl(byte),
_ => unreachable!(),
}
}
}
/// This trait abstracts away serializing the JSON control characters, which allows the user to
/// optionally pretty print the JSON output.
pub trait Formatter {
/// Writes a `null` value to the specified writer.
#[inline]
fn write_null<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"null")
}
/// Writes a `true` or `false` value to the specified writer.
#[inline]
fn write_bool<W>(&mut self, writer: &mut W, value: bool) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let s = if value {
b"true" as &[u8]
} else {
b"false" as &[u8]
};
writer.write_all(s)
}
/// Writes an integer value like `-123` to the specified writer.
#[inline]
fn write_i8<W>(&mut self, writer: &mut W, value: i8) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `-123` to the specified writer.
#[inline]
fn write_i16<W>(&mut self, writer: &mut W, value: i16) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `-123` to the specified writer.
#[inline]
fn write_i32<W>(&mut self, writer: &mut W, value: i32) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `-123` to the specified writer.
#[inline]
fn write_i64<W>(&mut self, writer: &mut W, value: i64) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `-123` to the specified writer.
#[inline]
fn write_i128<W>(&mut self, writer: &mut W, value: i128) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `123` to the specified writer.
#[inline]
fn write_u8<W>(&mut self, writer: &mut W, value: u8) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `123` to the specified writer.
#[inline]
fn write_u16<W>(&mut self, writer: &mut W, value: u16) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `123` to the specified writer.
#[inline]
fn write_u32<W>(&mut self, writer: &mut W, value: u32) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `123` to the specified writer.
#[inline]
fn write_u64<W>(&mut self, writer: &mut W, value: u64) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes an integer value like `123` to the specified writer.
#[inline]
fn write_u128<W>(&mut self, writer: &mut W, value: u128) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = itoa::Buffer::new();
let s = buffer.format(value);
writer.write_all(s.as_bytes())
}
/// Writes a floating point value like `-31.26e+12` to the specified writer.
#[inline]
fn write_f32<W>(&mut self, writer: &mut W, value: f32) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = ryu::Buffer::new();
let s = buffer.format_finite(value);
writer.write_all(s.as_bytes())
}
/// Writes a floating point value like `-31.26e+12` to the specified writer.
#[inline]
fn write_f64<W>(&mut self, writer: &mut W, value: f64) -> io::Result<()>
where
W: ?Sized + io::Write,
{
let mut buffer = ryu::Buffer::new();
let s = buffer.format_finite(value);
writer.write_all(s.as_bytes())
}
/// Writes a number that has already been rendered to a string.
#[inline]
fn write_number_str<W>(&mut self, writer: &mut W, value: &str) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(value.as_bytes())
}
/// Called before each series of `write_string_fragment` and
/// `write_char_escape`. Writes a `"` to the specified writer.
#[inline]
fn begin_string<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"\"")
}
/// Called after each series of `write_string_fragment` and
/// `write_char_escape`. Writes a `"` to the specified writer.
#[inline]
fn end_string<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"\"")
}
/// Writes a string fragment that doesn't need any escaping to the
/// specified writer.
#[inline]
fn write_string_fragment<W>(&mut self, writer: &mut W, fragment: &str) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(fragment.as_bytes())
}
/// Writes a character escape code to the specified writer.
#[inline]
fn write_char_escape<W>(&mut self, writer: &mut W, char_escape: CharEscape) -> io::Result<()>
where
W: ?Sized + io::Write,
{
use self::CharEscape::*;
let s = match char_escape {
Quote => b"\\\"",
ReverseSolidus => b"\\\\",
Solidus => b"\\/",
Backspace => b"\\b",
FormFeed => b"\\f",
LineFeed => b"\\n",
CarriageReturn => b"\\r",
Tab => b"\\t",
AsciiControl(byte) => {
static HEX_DIGITS: [u8; 16] = *b"0123456789abcdef";
let bytes = &[
b'\\',
b'u',
b'0',
b'0',
HEX_DIGITS[(byte >> 4) as usize],
HEX_DIGITS[(byte & 0xF) as usize],
];
return writer.write_all(bytes);
}
};
writer.write_all(s)
}
/// Writes the representation of a byte array. Formatters can choose whether
/// to represent bytes as a JSON array of integers (the default), or some
/// JSON string encoding like hex or base64.
fn write_byte_array<W>(&mut self, writer: &mut W, value: &[u8]) -> io::Result<()>
where
W: ?Sized + io::Write,
{
tri!(self.begin_array(writer));
let mut first = true;
for byte in value {
tri!(self.begin_array_value(writer, first));
tri!(self.write_u8(writer, *byte));
tri!(self.end_array_value(writer));
first = false;
}
self.end_array(writer)
}
/// Called before every array. Writes a `[` to the specified
/// writer.
#[inline]
fn begin_array<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"[")
}
/// Called after every array. Writes a `]` to the specified
/// writer.
#[inline]
fn end_array<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"]")
}
/// Called before every array value. Writes a `,` if needed to
/// the specified writer.
#[inline]
fn begin_array_value<W>(&mut self, writer: &mut W, first: bool) -> io::Result<()>
where
W: ?Sized + io::Write,
{
if first {
Ok(())
} else {
writer.write_all(b",")
}
}
/// Called after every array value.
#[inline]
fn end_array_value<W>(&mut self, _writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
Ok(())
}
/// Called before every object. Writes a `{` to the specified
/// writer.
#[inline]
fn begin_object<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"{")
}
/// Called after every object. Writes a `}` to the specified
/// writer.
#[inline]
fn end_object<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b"}")
}
/// Called before every object key.
#[inline]
fn begin_object_key<W>(&mut self, writer: &mut W, first: bool) -> io::Result<()>
where
W: ?Sized + io::Write,
{
if first {
Ok(())
} else {
writer.write_all(b",")
}
}
/// Called after every object key. A `:` should be written to the
/// specified writer by either this method or
/// `begin_object_value`.
#[inline]
fn end_object_key<W>(&mut self, _writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
Ok(())
}
/// Called before every object value. A `:` should be written to
/// the specified writer by either this method or
/// `end_object_key`.
#[inline]
fn begin_object_value<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b":")
}
/// Called after every object value.
#[inline]
fn end_object_value<W>(&mut self, _writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
Ok(())
}
/// Writes a raw JSON fragment that doesn't need any escaping to the
/// specified writer.
#[inline]
fn write_raw_fragment<W>(&mut self, writer: &mut W, fragment: &str) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(fragment.as_bytes())
}
}
/// This structure compacts a JSON value with no extra whitespace.
#[derive(Clone, Debug)]
pub struct CompactFormatter;
impl Formatter for CompactFormatter {}
/// This structure pretty prints a JSON value to make it human readable.
#[derive(Clone, Debug)]
pub struct PrettyFormatter<'a> {
current_indent: usize,
has_value: bool,
indent: &'a [u8],
}
impl<'a> PrettyFormatter<'a> {
/// Construct a pretty printer formatter that defaults to using two spaces for indentation.
pub fn new() -> Self {
PrettyFormatter::with_indent(b" ")
}
/// Construct a pretty printer formatter that uses the `indent` string for indentation.
pub fn with_indent(indent: &'a [u8]) -> Self {
PrettyFormatter {
current_indent: 0,
has_value: false,
indent,
}
}
}
impl<'a> Default for PrettyFormatter<'a> {
fn default() -> Self {
PrettyFormatter::new()
}
}
impl<'a> Formatter for PrettyFormatter<'a> {
#[inline]
fn begin_array<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.current_indent += 1;
self.has_value = false;
writer.write_all(b"[")
}
#[inline]
fn end_array<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.current_indent -= 1;
if self.has_value {
tri!(writer.write_all(b"\n"));
tri!(indent(writer, self.current_indent, self.indent));
}
writer.write_all(b"]")
}
#[inline]
fn begin_array_value<W>(&mut self, writer: &mut W, first: bool) -> io::Result<()>
where
W: ?Sized + io::Write,
{
tri!(writer.write_all(if first { b"\n" } else { b",\n" }));
indent(writer, self.current_indent, self.indent)
}
#[inline]
fn end_array_value<W>(&mut self, _writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.has_value = true;
Ok(())
}
#[inline]
fn begin_object<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.current_indent += 1;
self.has_value = false;
writer.write_all(b"{")
}
#[inline]
fn end_object<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.current_indent -= 1;
if self.has_value {
tri!(writer.write_all(b"\n"));
tri!(indent(writer, self.current_indent, self.indent));
}
writer.write_all(b"}")
}
#[inline]
fn begin_object_key<W>(&mut self, writer: &mut W, first: bool) -> io::Result<()>
where
W: ?Sized + io::Write,
{
tri!(writer.write_all(if first { b"\n" } else { b",\n" }));
indent(writer, self.current_indent, self.indent)
}
#[inline]
fn begin_object_value<W>(&mut self, writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
writer.write_all(b": ")
}
#[inline]
fn end_object_value<W>(&mut self, _writer: &mut W) -> io::Result<()>
where
W: ?Sized + io::Write,
{
self.has_value = true;
Ok(())
}
}
fn format_escaped_str<W, F>(writer: &mut W, formatter: &mut F, value: &str) -> io::Result<()>
where
W: ?Sized + io::Write,
F: ?Sized + Formatter,
{
tri!(formatter.begin_string(writer));
tri!(format_escaped_str_contents(writer, formatter, value));
formatter.end_string(writer)
}
fn format_escaped_str_contents<W, F>(
writer: &mut W,
formatter: &mut F,
value: &str,
) -> io::Result<()>
where
W: ?Sized + io::Write,
F: ?Sized + Formatter,
{
let bytes = value.as_bytes();
let mut start = 0;
for (i, &byte) in bytes.iter().enumerate() {
let escape = ESCAPE[byte as usize];
if escape == 0 {
continue;
}
if start < i {
tri!(formatter.write_string_fragment(writer, &value[start..i]));
}
let char_escape = CharEscape::from_escape_table(escape, byte);
tri!(formatter.write_char_escape(writer, char_escape));
start = i + 1;
}
if start == bytes.len() {
return Ok(());
}
formatter.write_string_fragment(writer, &value[start..])
}
const BB: u8 = b'b'; // \x08
const TT: u8 = b't'; // \x09
const NN: u8 = b'n'; // \x0A
const FF: u8 = b'f'; // \x0C
const RR: u8 = b'r'; // \x0D
const QU: u8 = b'"'; // \x22
const BS: u8 = b'\\'; // \x5C
const UU: u8 = b'u'; // \x00...\x1F except the ones above
const __: u8 = 0;
// Lookup table of escape sequences. A value of b'x' at index i means that byte
// i is escaped as "\x" in JSON. A value of 0 means that byte i is not escaped.
static ESCAPE: [u8; 256] = [
// 1 2 3 4 5 6 7 8 9 A B C D E F
UU, UU, UU, UU, UU, UU, UU, UU, BB, TT, NN, UU, FF, RR, UU, UU, // 0
UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, UU, // 1
__, __, QU, __, __, __, __, __, __, __, __, __, __, __, __, __, // 2
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 3
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 4
__, __, __, __, __, __, __, __, __, __, __, __, BS, __, __, __, // 5
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 6
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 7
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 8
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // 9
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // A
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // B
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // C
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // D
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // E
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __, // F
];
/// Serialize the given data structure as JSON into the I/O stream.
///
/// Serialization guarantees it only feeds valid UTF-8 sequences to the writer.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
pub fn to_writer<W, T>(writer: W, value: &T) -> Result<()>
where
W: io::Write,
T: ?Sized + Serialize,
{
let mut ser = Serializer::new(writer);
value.serialize(&mut ser)
}
/// Serialize the given data structure as pretty-printed JSON into the I/O
/// stream.
///
/// Serialization guarantees it only feeds valid UTF-8 sequences to the writer.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
pub fn to_writer_pretty<W, T>(writer: W, value: &T) -> Result<()>
where
W: io::Write,
T: ?Sized + Serialize,
{
let mut ser = Serializer::pretty(writer);
value.serialize(&mut ser)
}
/// Serialize the given data structure as a JSON byte vector.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
pub fn to_vec<T>(value: &T) -> Result<Vec<u8>>
where
T: ?Sized + Serialize,
{
let mut writer = Vec::with_capacity(128);
tri!(to_writer(&mut writer, value));
Ok(writer)
}
/// Serialize the given data structure as a pretty-printed JSON byte vector.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
pub fn to_vec_pretty<T>(value: &T) -> Result<Vec<u8>>
where
T: ?Sized + Serialize,
{
let mut writer = Vec::with_capacity(128);
tri!(to_writer_pretty(&mut writer, value));
Ok(writer)
}
/// Serialize the given data structure as a String of JSON.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
pub fn to_string<T>(value: &T) -> Result<String>
where
T: ?Sized + Serialize,
{
let vec = tri!(to_vec(value));
let string = unsafe {
// We do not emit invalid UTF-8.
String::from_utf8_unchecked(vec)
};
Ok(string)
}
/// Serialize the given data structure as a pretty-printed String of JSON.
///
/// # Errors
///
/// Serialization can fail if `T`'s implementation of `Serialize` decides to
/// fail, or if `T` contains a map with non-string keys.
#[inline]
pub fn to_string_pretty<T>(value: &T) -> Result<String>
where
T: ?Sized + Serialize,
{
let vec = tri!(to_vec_pretty(value));
let string = unsafe {
// We do not emit invalid UTF-8.
String::from_utf8_unchecked(vec)
};
Ok(string)
}
fn indent<W>(wr: &mut W, n: usize, s: &[u8]) -> io::Result<()>
where
W: ?Sized + io::Write,
{
for _ in 0..n {
tri!(wr.write_all(s));
}
Ok(())
}