mod deserializer;
mod serializer;
use std::{convert::TryFrom, f64::NAN, fmt};
use std::{collections::HashMap, hash::Hash};
pub use self::{
deserializer::{from_value, from_value_owned},
serializer::to_value,
};
#[derive(Clone, Debug, PartialEq)]
pub enum Value {
Null,
Bool(bool),
I64(i64),
F64(f64),
String(String),
U8List(Vec<u8>),
I32List(Vec<i32>),
I64List(Vec<i64>),
F64List(Vec<f64>),
List(Vec<Value>),
Map(HashMap<Value, Value>),
}
impl Default for Value {
fn default() -> Self {
Value::Null
}
}
macro_rules! impl_from {
($variant:path, $for_type:ty) => {
impl From<$for_type> for Value {
fn from(v: $for_type) -> Value {
$variant(v.into())
}
}
};
}
impl_from!(Value::Bool, bool);
impl_from!(Value::I64, i64);
impl_from!(Value::I64, u32);
impl_from!(Value::F64, f32);
impl_from!(Value::F64, f64);
impl_from!(Value::String, String);
impl_from!(Value::String, &str);
impl_from!(Value::U8List, Vec<u8>);
impl_from!(Value::I32List, Vec<i32>);
impl_from!(Value::I64List, Vec<i64>);
impl_from!(Value::F64List, Vec<f64>);
impl_from!(Value::List, Vec<Value>);
impl_from!(Value::Map, HashMap<Value, Value>);
impl Eq for Value {}
fn hash_f64<H: std::hash::Hasher>(value: f64, state: &mut H) {
let value: f64 = if value.is_nan() { NAN } else { value };
let transmuted: u64 = value.to_bits();
state.write_u64(transmuted);
}
fn hash_map<H: std::hash::Hasher>(map: &HashMap<Value, Value>, state: &mut H) {
for (key, value) in map {
key.hash(state);
value.hash(state);
}
}
#[allow(clippy::derive_hash_xor_eq)]
impl std::hash::Hash for Value {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
match self {
Value::Null => state.write_u64(640),
Value::Bool(v) => v.hash(state),
Value::I64(v) => v.hash(state),
Value::F64(v) => hash_f64(*v, state),
Value::String(v) => v.hash(state),
Value::U8List(v) => v.hash(state),
Value::I32List(v) => v.hash(state),
Value::I64List(v) => v.hash(state),
Value::F64List(v) => v.iter().for_each(|x| hash_f64(*x, state)),
Value::List(v) => v.hash(state),
Value::Map(v) => hash_map(v, state),
}
}
}
#[derive(Debug, Clone)]
pub enum ValueError {
Message(String),
ConversionError,
WrongType,
NoList,
NoMap,
}
impl fmt::Display for ValueError {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
match self {
ValueError::Message(s) => write!(f, "{}", s),
ValueError::ConversionError => write!(f, "Value can't be converted to target type"),
ValueError::WrongType => write!(f, "Value is of wrong type"),
ValueError::NoList => write!(f, "Value is not a list"),
ValueError::NoMap => write!(f, "Value is not a map"),
}
}
}
impl serde::ser::Error for ValueError {
fn custom<T>(msg: T) -> Self
where
T: fmt::Display,
{
ValueError::Message(msg.to_string())
}
}
impl serde::de::Error for ValueError {
fn custom<T: fmt::Display>(msg: T) -> Self {
ValueError::Message(msg.to_string())
}
}
impl std::error::Error for ValueError {}
impl serde::Serialize for Value {
#[inline]
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::Serializer,
{
match self {
Value::Null => serializer.serialize_unit(),
Value::Bool(b) => serializer.serialize_bool(*b),
Value::I64(i) => serializer.serialize_i64(*i),
Value::F64(f) => serializer.serialize_f64(*f),
Value::String(s) => serializer.serialize_str(s.as_str()),
Value::U8List(vec) => serializer.serialize_bytes(vec),
Value::I32List(vec) => vec.serialize(serializer),
Value::I64List(vec) => vec.serialize(serializer),
Value::F64List(vec) => vec.serialize(serializer),
Value::List(vec) => vec.serialize(serializer),
Value::Map(map) => {
use serde::ser::SerializeMap;
let mut m = serializer.serialize_map(Some(map.len()))?;
for (k, v) in map {
m.serialize_entry(k, v)?;
}
m.end()
}
}
}
}
struct ValueVisitor;
impl<'de> serde::de::Visitor<'de> for ValueVisitor {
type Value = Value;
fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
formatter.write_str("any valid JSON value")
}
#[inline]
fn visit_bool<E>(self, value: bool) -> Result<Value, E> {
Ok(Value::Bool(value))
}
#[inline]
fn visit_i64<E>(self, value: i64) -> Result<Value, E> {
Ok(Value::I64(value))
}
#[inline]
fn visit_u64<E>(self, value: u64) -> Result<Value, E>
where
E: serde::de::Error,
{
if let Ok(i) = i64::try_from(value) {
Ok(Value::I64(i))
} else {
Err(E::custom("Number too large for i64"))
}
}
#[inline]
fn visit_f64<E>(self, value: f64) -> Result<Value, E> {
Ok(Value::F64(value))
}
#[inline]
fn visit_str<E>(self, value: &str) -> Result<Value, E> {
Ok(Value::String(value.into()))
}
#[inline]
fn visit_string<E>(self, value: String) -> Result<Value, E> {
Ok(Value::String(value))
}
#[inline]
fn visit_bytes<E>(self, v: &[u8]) -> Result<Value, E> {
Ok(Value::U8List(v.into()))
}
#[inline]
fn visit_none<E>(self) -> Result<Value, E> {
Ok(Value::Null)
}
#[inline]
fn visit_some<D>(self, deserializer: D) -> Result<Value, D::Error>
where
D: serde::de::Deserializer<'de>,
{
serde::Deserialize::deserialize(deserializer)
}
#[inline]
fn visit_unit<E>(self) -> Result<Value, E> {
Ok(Value::Null)
}
#[inline]
fn visit_seq<V>(self, mut visitor: V) -> Result<Value, V::Error>
where
V: serde::de::SeqAccess<'de>,
{
let mut vec = Vec::new();
while let Some(elem) = visitor.next_element()? {
vec.push(elem);
}
Ok(Value::List(vec))
}
#[inline]
fn visit_map<V>(self, mut visitor: V) -> Result<Value, V::Error>
where
V: serde::de::MapAccess<'de>,
{
let mut map = HashMap::new();
while let Some((k, v)) = visitor.next_entry()? {
map.insert(k, v);
}
Ok(Value::Map(map))
}
}
impl<'de> serde::Deserialize<'de> for Value {
#[inline]
fn deserialize<D>(deserializer: D) -> Result<Value, D::Error>
where
D: serde::de::Deserializer<'de>,
{
deserializer.deserialize_any(ValueVisitor)
}
}