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use crate::de::ParserNumber;
use crate::error::Error;
#[cfg(feature = "arbitrary_precision")]
use crate::error::ErrorCode;
#[cfg(feature = "arbitrary_precision")]
use alloc::borrow::ToOwned;
#[cfg(feature = "arbitrary_precision")]
use alloc::string::{String, ToString};
use core::fmt::{self, Debug, Display};
#[cfg(not(feature = "arbitrary_precision"))]
use core::hash::{Hash, Hasher};
use serde::de::{self, Unexpected, Visitor};
#[cfg(feature = "arbitrary_precision")]
use serde::de::{IntoDeserializer, MapAccess};
use serde::{forward_to_deserialize_any, Deserialize, Deserializer, Serialize, Serializer};
#[cfg(feature = "arbitrary_precision")]
pub(crate) const TOKEN: &str = "$serde_json::private::Number";
/// Represents a JSON number, whether integer or floating point.
#[derive(Clone, PartialEq, Eq, Hash)]
pub struct Number {
n: N,
}
#[cfg(not(feature = "arbitrary_precision"))]
#[derive(Copy, Clone)]
enum N {
PosInt(u64),
/// Always less than zero.
NegInt(i64),
/// Always finite.
Float(f64),
}
#[cfg(not(feature = "arbitrary_precision"))]
impl PartialEq for N {
fn eq(&self, other: &Self) -> bool {
match (self, other) {
(N::PosInt(a), N::PosInt(b)) => a == b,
(N::NegInt(a), N::NegInt(b)) => a == b,
(N::Float(a), N::Float(b)) => a == b,
_ => false,
}
}
}
// Implementing Eq is fine since any float values are always finite.
#[cfg(not(feature = "arbitrary_precision"))]
impl Eq for N {}
#[cfg(not(feature = "arbitrary_precision"))]
impl Hash for N {
fn hash<H: Hasher>(&self, h: &mut H) {
match *self {
N::PosInt(i) => i.hash(h),
N::NegInt(i) => i.hash(h),
N::Float(f) => {
if f == 0.0f64 {
// There are 2 zero representations, +0 and -0, which
// compare equal but have different bits. We use the +0 hash
// for both so that hash(+0) == hash(-0).
0.0f64.to_bits().hash(h);
} else {
f.to_bits().hash(h);
}
}
}
}
}
#[cfg(feature = "arbitrary_precision")]
type N = String;
impl Number {
/// Returns true if the `Number` is an integer between `i64::MIN` and
/// `i64::MAX`.
///
/// For any Number on which `is_i64` returns true, `as_i64` is guaranteed to
/// return the integer value.
///
/// ```
/// # use serde_json::json;
/// #
/// let big = i64::MAX as u64 + 10;
/// let v = json!({ "a": 64, "b": big, "c": 256.0 });
///
/// assert!(v["a"].is_i64());
///
/// // Greater than i64::MAX.
/// assert!(!v["b"].is_i64());
///
/// // Numbers with a decimal point are not considered integers.
/// assert!(!v["c"].is_i64());
/// ```
#[inline]
pub fn is_i64(&self) -> bool {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(v) => v <= i64::MAX as u64,
N::NegInt(_) => true,
N::Float(_) => false,
}
#[cfg(feature = "arbitrary_precision")]
self.as_i64().is_some()
}
/// Returns true if the `Number` is an integer between zero and `u64::MAX`.
///
/// For any Number on which `is_u64` returns true, `as_u64` is guaranteed to
/// return the integer value.
///
/// ```
/// # use serde_json::json;
/// #
/// let v = json!({ "a": 64, "b": -64, "c": 256.0 });
///
/// assert!(v["a"].is_u64());
///
/// // Negative integer.
/// assert!(!v["b"].is_u64());
///
/// // Numbers with a decimal point are not considered integers.
/// assert!(!v["c"].is_u64());
/// ```
#[inline]
pub fn is_u64(&self) -> bool {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(_) => true,
N::NegInt(_) | N::Float(_) => false,
}
#[cfg(feature = "arbitrary_precision")]
self.as_u64().is_some()
}
/// Returns true if the `Number` can be represented by f64.
///
/// For any Number on which `is_f64` returns true, `as_f64` is guaranteed to
/// return the floating point value.
///
/// Currently this function returns true if and only if both `is_i64` and
/// `is_u64` return false but this is not a guarantee in the future.
///
/// ```
/// # use serde_json::json;
/// #
/// let v = json!({ "a": 256.0, "b": 64, "c": -64 });
///
/// assert!(v["a"].is_f64());
///
/// // Integers.
/// assert!(!v["b"].is_f64());
/// assert!(!v["c"].is_f64());
/// ```
#[inline]
pub fn is_f64(&self) -> bool {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::Float(_) => true,
N::PosInt(_) | N::NegInt(_) => false,
}
#[cfg(feature = "arbitrary_precision")]
{
for c in self.n.chars() {
if c == '.' || c == 'e' || c == 'E' {
return self.n.parse::<f64>().ok().map_or(false, f64::is_finite);
}
}
false
}
}
/// If the `Number` is an integer, represent it as i64 if possible. Returns
/// None otherwise.
///
/// ```
/// # use serde_json::json;
/// #
/// let big = i64::MAX as u64 + 10;
/// let v = json!({ "a": 64, "b": big, "c": 256.0 });
///
/// assert_eq!(v["a"].as_i64(), Some(64));
/// assert_eq!(v["b"].as_i64(), None);
/// assert_eq!(v["c"].as_i64(), None);
/// ```
#[inline]
pub fn as_i64(&self) -> Option<i64> {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(n) => {
if n <= i64::MAX as u64 {
Some(n as i64)
} else {
None
}
}
N::NegInt(n) => Some(n),
N::Float(_) => None,
}
#[cfg(feature = "arbitrary_precision")]
self.n.parse().ok()
}
/// If the `Number` is an integer, represent it as u64 if possible. Returns
/// None otherwise.
///
/// ```
/// # use serde_json::json;
/// #
/// let v = json!({ "a": 64, "b": -64, "c": 256.0 });
///
/// assert_eq!(v["a"].as_u64(), Some(64));
/// assert_eq!(v["b"].as_u64(), None);
/// assert_eq!(v["c"].as_u64(), None);
/// ```
#[inline]
pub fn as_u64(&self) -> Option<u64> {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(n) => Some(n),
N::NegInt(_) | N::Float(_) => None,
}
#[cfg(feature = "arbitrary_precision")]
self.n.parse().ok()
}
/// Represents the number as f64 if possible. Returns None otherwise.
///
/// ```
/// # use serde_json::json;
/// #
/// let v = json!({ "a": 256.0, "b": 64, "c": -64 });
///
/// assert_eq!(v["a"].as_f64(), Some(256.0));
/// assert_eq!(v["b"].as_f64(), Some(64.0));
/// assert_eq!(v["c"].as_f64(), Some(-64.0));
/// ```
#[inline]
pub fn as_f64(&self) -> Option<f64> {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(n) => Some(n as f64),
N::NegInt(n) => Some(n as f64),
N::Float(n) => Some(n),
}
#[cfg(feature = "arbitrary_precision")]
self.n.parse::<f64>().ok().filter(|float| float.is_finite())
}
/// Converts a finite `f64` to a `Number`. Infinite or NaN values are not JSON
/// numbers.
///
/// ```
/// # use std::f64;
/// #
/// # use serde_json::Number;
/// #
/// assert!(Number::from_f64(256.0).is_some());
///
/// assert!(Number::from_f64(f64::NAN).is_none());
/// ```
#[inline]
pub fn from_f64(f: f64) -> Option<Number> {
if f.is_finite() {
let n = {
#[cfg(not(feature = "arbitrary_precision"))]
{
N::Float(f)
}
#[cfg(feature = "arbitrary_precision")]
{
ryu::Buffer::new().format_finite(f).to_owned()
}
};
Some(Number { n })
} else {
None
}
}
/// Returns the exact original JSON representation that this Number was
/// parsed from.
///
/// For numbers constructed not via parsing, such as by `From<i32>`, returns
/// the JSON representation that serde\_json would serialize for this
/// number.
///
/// ```
/// # use serde_json::Number;
/// for value in [
/// "7",
/// "12.34",
/// "34e-56789",
/// "0.0123456789000000012345678900000001234567890000123456789",
/// "343412345678910111213141516171819202122232425262728293034",
/// "-343412345678910111213141516171819202122232425262728293031",
/// ] {
/// let number: Number = serde_json::from_str(value).unwrap();
/// assert_eq!(number.as_str(), value);
/// }
/// ```
#[cfg(feature = "arbitrary_precision")]
#[cfg_attr(docsrs, doc(cfg(feature = "arbitrary_precision")))]
pub fn as_str(&self) -> &str {
&self.n
}
pub(crate) fn as_f32(&self) -> Option<f32> {
#[cfg(not(feature = "arbitrary_precision"))]
match self.n {
N::PosInt(n) => Some(n as f32),
N::NegInt(n) => Some(n as f32),
N::Float(n) => Some(n as f32),
}
#[cfg(feature = "arbitrary_precision")]
self.n.parse::<f32>().ok().filter(|float| float.is_finite())
}
pub(crate) fn from_f32(f: f32) -> Option<Number> {
if f.is_finite() {
let n = {
#[cfg(not(feature = "arbitrary_precision"))]
{
N::Float(f as f64)
}
#[cfg(feature = "arbitrary_precision")]
{
ryu::Buffer::new().format_finite(f).to_owned()
}
};
Some(Number { n })
} else {
None
}
}
#[cfg(feature = "arbitrary_precision")]
/// Not public API. Only tests use this.
#[doc(hidden)]
#[inline]
pub fn from_string_unchecked(n: String) -> Self {
Number { n }
}
}
impl Display for Number {
#[cfg(not(feature = "arbitrary_precision"))]
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
match self.n {
N::PosInt(u) => formatter.write_str(itoa::Buffer::new().format(u)),
N::NegInt(i) => formatter.write_str(itoa::Buffer::new().format(i)),
N::Float(f) => formatter.write_str(ryu::Buffer::new().format_finite(f)),
}
}
#[cfg(feature = "arbitrary_precision")]
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
Display::fmt(&self.n, formatter)
}
}
impl Debug for Number {
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
write!(formatter, "Number({})", self)
}
}
impl Serialize for Number {
#[cfg(not(feature = "arbitrary_precision"))]
#[inline]
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
match self.n {
N::PosInt(u) => serializer.serialize_u64(u),
N::NegInt(i) => serializer.serialize_i64(i),
N::Float(f) => serializer.serialize_f64(f),
}
}
#[cfg(feature = "arbitrary_precision")]
#[inline]
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: Serializer,
{
use serde::ser::SerializeStruct;
let mut s = tri!(serializer.serialize_struct(TOKEN, 1));
tri!(s.serialize_field(TOKEN, &self.n));
s.end()
}
}
impl<'de> Deserialize<'de> for Number {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Number, D::Error>
where
D: Deserializer<'de>,
{
struct NumberVisitor;
impl<'de> Visitor<'de> for NumberVisitor {
type Value = Number;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a JSON number")
}
#[inline]
fn visit_i64<E>(self, value: i64) -> Result<Number, E> {
Ok(value.into())
}
#[inline]
fn visit_u64<E>(self, value: u64) -> Result<Number, E> {
Ok(value.into())
}
#[inline]
fn visit_f64<E>(self, value: f64) -> Result<Number, E>
where
E: de::Error,
{
Number::from_f64(value).ok_or_else(|| de::Error::custom("not a JSON number"))
}
#[cfg(feature = "arbitrary_precision")]
#[inline]
fn visit_map<V>(self, mut visitor: V) -> Result<Number, V::Error>
where
V: de::MapAccess<'de>,
{
let value = tri!(visitor.next_key::<NumberKey>());
if value.is_none() {
return Err(de::Error::invalid_type(Unexpected::Map, &self));
}
let v: NumberFromString = tri!(visitor.next_value());
Ok(v.value)
}
}
deserializer.deserialize_any(NumberVisitor)
}
}
#[cfg(feature = "arbitrary_precision")]
struct NumberKey;
#[cfg(feature = "arbitrary_precision")]
impl<'de> de::Deserialize<'de> for NumberKey {
fn deserialize<D>(deserializer: D) -> Result<NumberKey, D::Error>
where
D: de::Deserializer<'de>,
{
struct FieldVisitor;
impl<'de> de::Visitor<'de> for FieldVisitor {
type Value = ();
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a valid number field")
}
fn visit_str<E>(self, s: &str) -> Result<(), E>
where
E: de::Error,
{
if s == TOKEN {
Ok(())
} else {
Err(de::Error::custom("expected field with custom name"))
}
}
}
tri!(deserializer.deserialize_identifier(FieldVisitor));
Ok(NumberKey)
}
}
#[cfg(feature = "arbitrary_precision")]
pub struct NumberFromString {
pub value: Number,
}
#[cfg(feature = "arbitrary_precision")]
impl<'de> de::Deserialize<'de> for NumberFromString {
fn deserialize<D>(deserializer: D) -> Result<NumberFromString, D::Error>
where
D: de::Deserializer<'de>,
{
struct Visitor;
impl<'de> de::Visitor<'de> for Visitor {
type Value = NumberFromString;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("string containing a number")
}
fn visit_str<E>(self, s: &str) -> Result<NumberFromString, E>
where
E: de::Error,
{
let n = tri!(s.parse().map_err(de::Error::custom));
Ok(NumberFromString { value: n })
}
}
deserializer.deserialize_str(Visitor)
}
}
#[cfg(feature = "arbitrary_precision")]
fn invalid_number() -> Error {
Error::syntax(ErrorCode::InvalidNumber, 0, 0)
}
macro_rules! deserialize_any {
(@expand [$($num_string:tt)*]) => {
#[cfg(not(feature = "arbitrary_precision"))]
#[inline]
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: Visitor<'de>,
{
match self.n {
N::PosInt(u) => visitor.visit_u64(u),
N::NegInt(i) => visitor.visit_i64(i),
N::Float(f) => visitor.visit_f64(f),
}
}
#[cfg(feature = "arbitrary_precision")]
#[inline]
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Error>
where V: Visitor<'de>
{
if let Some(u) = self.as_u64() {
return visitor.visit_u64(u);
} else if let Some(i) = self.as_i64() {
return visitor.visit_i64(i);
} else if let Some(f) = self.as_f64() {
if ryu::Buffer::new().format_finite(f) == self.n || f.to_string() == self.n {
return visitor.visit_f64(f);
}
}
visitor.visit_map(NumberDeserializer {
number: Some(self.$($num_string)*),
})
}
};
(owned) => {
deserialize_any!(@expand [n]);
};
(ref) => {
deserialize_any!(@expand [n.clone()]);
};
}
macro_rules! deserialize_number {
($deserialize:ident => $visit:ident) => {
#[cfg(not(feature = "arbitrary_precision"))]
fn $deserialize<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: Visitor<'de>,
{
self.deserialize_any(visitor)
}
#[cfg(feature = "arbitrary_precision")]
fn $deserialize<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
visitor.$visit(tri!(self.n.parse().map_err(|_| invalid_number())))
}
};
}
impl<'de> Deserializer<'de> for Number {
type Error = Error;
deserialize_any!(owned);
deserialize_number!(deserialize_i8 => visit_i8);
deserialize_number!(deserialize_i16 => visit_i16);
deserialize_number!(deserialize_i32 => visit_i32);
deserialize_number!(deserialize_i64 => visit_i64);
deserialize_number!(deserialize_i128 => visit_i128);
deserialize_number!(deserialize_u8 => visit_u8);
deserialize_number!(deserialize_u16 => visit_u16);
deserialize_number!(deserialize_u32 => visit_u32);
deserialize_number!(deserialize_u64 => visit_u64);
deserialize_number!(deserialize_u128 => visit_u128);
deserialize_number!(deserialize_f32 => visit_f32);
deserialize_number!(deserialize_f64 => visit_f64);
forward_to_deserialize_any! {
bool char str string bytes byte_buf option unit unit_struct
newtype_struct seq tuple tuple_struct map struct enum identifier
ignored_any
}
}
impl<'de, 'a> Deserializer<'de> for &'a Number {
type Error = Error;
deserialize_any!(ref);
deserialize_number!(deserialize_i8 => visit_i8);
deserialize_number!(deserialize_i16 => visit_i16);
deserialize_number!(deserialize_i32 => visit_i32);
deserialize_number!(deserialize_i64 => visit_i64);
deserialize_number!(deserialize_i128 => visit_i128);
deserialize_number!(deserialize_u8 => visit_u8);
deserialize_number!(deserialize_u16 => visit_u16);
deserialize_number!(deserialize_u32 => visit_u32);
deserialize_number!(deserialize_u64 => visit_u64);
deserialize_number!(deserialize_u128 => visit_u128);
deserialize_number!(deserialize_f32 => visit_f32);
deserialize_number!(deserialize_f64 => visit_f64);
forward_to_deserialize_any! {
bool char str string bytes byte_buf option unit unit_struct
newtype_struct seq tuple tuple_struct map struct enum identifier
ignored_any
}
}
#[cfg(feature = "arbitrary_precision")]
pub(crate) struct NumberDeserializer {
pub number: Option<String>,
}
#[cfg(feature = "arbitrary_precision")]
impl<'de> MapAccess<'de> for NumberDeserializer {
type Error = Error;
fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Error>
where
K: de::DeserializeSeed<'de>,
{
if self.number.is_none() {
return Ok(None);
}
seed.deserialize(NumberFieldDeserializer).map(Some)
}
fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Error>
where
V: de::DeserializeSeed<'de>,
{
seed.deserialize(self.number.take().unwrap().into_deserializer())
}
}
#[cfg(feature = "arbitrary_precision")]
struct NumberFieldDeserializer;
#[cfg(feature = "arbitrary_precision")]
impl<'de> Deserializer<'de> for NumberFieldDeserializer {
type Error = Error;
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Error>
where
V: de::Visitor<'de>,
{
visitor.visit_borrowed_str(TOKEN)
}
forward_to_deserialize_any! {
bool u8 u16 u32 u64 u128 i8 i16 i32 i64 i128 f32 f64 char str string seq
bytes byte_buf map struct option unit newtype_struct ignored_any
unit_struct tuple_struct tuple enum identifier
}
}
impl From<ParserNumber> for Number {
fn from(value: ParserNumber) -> Self {
let n = match value {
ParserNumber::F64(f) => {
#[cfg(not(feature = "arbitrary_precision"))]
{
N::Float(f)
}
#[cfg(feature = "arbitrary_precision")]
{
f.to_string()
}
}
ParserNumber::U64(u) => {
#[cfg(not(feature = "arbitrary_precision"))]
{
N::PosInt(u)
}
#[cfg(feature = "arbitrary_precision")]
{
u.to_string()
}
}
ParserNumber::I64(i) => {
#[cfg(not(feature = "arbitrary_precision"))]
{
N::NegInt(i)
}
#[cfg(feature = "arbitrary_precision")]
{
i.to_string()
}
}
#[cfg(feature = "arbitrary_precision")]
ParserNumber::String(s) => s,
};
Number { n }
}
}
macro_rules! impl_from_unsigned {
(
$($ty:ty),*
) => {
$(
impl From<$ty> for Number {
#[inline]
fn from(u: $ty) -> Self {
let n = {
#[cfg(not(feature = "arbitrary_precision"))]
{ N::PosInt(u as u64) }
#[cfg(feature = "arbitrary_precision")]
{
itoa::Buffer::new().format(u).to_owned()
}
};
Number { n }
}
}
)*
};
}
macro_rules! impl_from_signed {
(
$($ty:ty),*
) => {
$(
impl From<$ty> for Number {
#[inline]
fn from(i: $ty) -> Self {
let n = {
#[cfg(not(feature = "arbitrary_precision"))]
{
if i < 0 {
N::NegInt(i as i64)
} else {
N::PosInt(i as u64)
}
}
#[cfg(feature = "arbitrary_precision")]
{
itoa::Buffer::new().format(i).to_owned()
}
};
Number { n }
}
}
)*
};
}
impl_from_unsigned!(u8, u16, u32, u64, usize);
impl_from_signed!(i8, i16, i32, i64, isize);
#[cfg(feature = "arbitrary_precision")]
impl_from_unsigned!(u128);
#[cfg(feature = "arbitrary_precision")]
impl_from_signed!(i128);
impl Number {
#[cfg(not(feature = "arbitrary_precision"))]
#[cold]
pub(crate) fn unexpected(&self) -> Unexpected {
match self.n {
N::PosInt(u) => Unexpected::Unsigned(u),
N::NegInt(i) => Unexpected::Signed(i),
N::Float(f) => Unexpected::Float(f),
}
}
#[cfg(feature = "arbitrary_precision")]
#[cold]
pub(crate) fn unexpected(&self) -> Unexpected {
Unexpected::Other("number")
}
}