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use std::fmt;
use serde::{
de::{Error, MapAccess, SeqAccess, Visitor},
Deserialize, Deserializer,
};
use crate::{
error::SpannedResult,
value::{Map, Number, Value},
};
impl std::str::FromStr for Value {
type Err = crate::error::SpannedError;
/// Creates a value from a string reference.
fn from_str(s: &str) -> SpannedResult<Self> {
let mut de = super::Deserializer::from_str(s)?;
let val = Value::deserialize(&mut de).map_err(|e| de.span_error(e))?;
de.end().map_err(|e| de.span_error(e))?;
Ok(val)
}
}
impl<'de> Deserialize<'de> for Value {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_any(ValueVisitor)
}
}
struct ValueVisitor;
impl<'de> Visitor<'de> for ValueVisitor {
type Value = Value;
fn expecting(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
write!(f, "a RON value")
}
fn visit_bool<E>(self, v: bool) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Bool(v))
}
fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Number(Number::new(v)))
}
#[cfg(feature = "integer128")]
fn visit_i128<E>(self, v: i128) -> Result<Self::Value, E>
where
E: Error,
{
self.visit_f64(v as f64)
}
fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Number(Number::new(v)))
}
#[cfg(feature = "integer128")]
fn visit_u128<E>(self, v: u128) -> Result<Self::Value, E>
where
E: Error,
{
self.visit_f64(v as f64)
}
fn visit_f64<E>(self, v: f64) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Number(Number::new(v)))
}
fn visit_char<E>(self, v: char) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Char(v))
}
fn visit_str<E>(self, v: &str) -> Result<Self::Value, E>
where
E: Error,
{
self.visit_string(v.to_owned())
}
fn visit_string<E>(self, v: String) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::String(v))
}
fn visit_bytes<E>(self, v: &[u8]) -> Result<Self::Value, E>
where
E: Error,
{
self.visit_byte_buf(v.to_vec())
}
fn visit_byte_buf<E>(self, v: Vec<u8>) -> Result<Self::Value, E>
where
E: Error,
{
self.visit_string(String::from_utf8(v).map_err(|e| Error::custom(format!("{}", e)))?)
}
fn visit_none<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Option(None))
}
fn visit_some<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
where
D: Deserializer<'de>,
{
Ok(Value::Option(Some(Box::new(
deserializer.deserialize_any(ValueVisitor)?,
))))
}
fn visit_unit<E>(self) -> Result<Self::Value, E>
where
E: Error,
{
Ok(Value::Unit)
}
fn visit_newtype_struct<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
where
D: Deserializer<'de>,
{
deserializer.deserialize_any(ValueVisitor)
}
fn visit_seq<A>(self, mut seq: A) -> Result<Self::Value, A::Error>
where
A: SeqAccess<'de>,
{
let mut vec = Vec::new();
if let Some(cap) = seq.size_hint() {
vec.reserve_exact(cap);
}
while let Some(x) = seq.next_element()? {
vec.push(x);
}
Ok(Value::Seq(vec))
}
fn visit_map<A>(self, mut map: A) -> Result<Self::Value, A::Error>
where
A: MapAccess<'de>,
{
let mut res: Map = Map::new();
while let Some(entry) = map.next_entry()? {
res.insert(entry.0, entry.1);
}
Ok(Value::Map(res))
}
}
#[cfg(test)]
mod tests {
use std::str::FromStr;
use super::*;
fn eval(s: &str) -> Value {
s.parse().expect("Failed to parse")
}
#[test]
fn test_none() {
assert_eq!(eval("None"), Value::Option(None));
}
#[test]
fn test_some() {
assert_eq!(eval("Some(())"), Value::Option(Some(Box::new(Value::Unit))));
assert_eq!(
eval("Some ( () )"),
Value::Option(Some(Box::new(Value::Unit)))
);
}
#[test]
fn test_tuples_basic() {
assert_eq!(
eval("(3, 4.0, 5.0)"),
Value::Seq(vec![
Value::Number(Number::new(3)),
Value::Number(Number::new(4.0)),
Value::Number(Number::new(5.0)),
],),
);
}
#[test]
fn test_tuples_ident() {
assert_eq!(
eval("(true, 3, 4, 5.0)"),
Value::Seq(vec![
Value::Bool(true),
Value::Number(Number::new(3)),
Value::Number(Number::new(4)),
Value::Number(Number::new(5.0)),
]),
);
}
#[test]
fn test_tuples_error() {
use crate::de::{Error, Position, SpannedError};
assert_eq!(
Value::from_str("Foo:").unwrap_err(),
SpannedError {
code: Error::TrailingCharacters,
position: Position { col: 4, line: 1 }
},
);
}
#[test]
fn test_floats() {
assert_eq!(
eval("(inf, -inf, NaN)"),
Value::Seq(vec![
Value::Number(Number::new(std::f64::INFINITY)),
Value::Number(Number::new(std::f64::NEG_INFINITY)),
Value::Number(Number::new(std::f64::NAN)),
]),
);
}
#[test]
fn test_complex() {
assert_eq!(
eval(
"Some([
Room ( width: 20, height: 5, name: \"The Room\" ),
(
width: 10.0,
height: 10.0,
name: \"Another room\",
enemy_levels: {
\"Enemy1\": 3,
\"Enemy2\": 5,
\"Enemy3\": 7,
},
),
])"
),
Value::Option(Some(Box::new(Value::Seq(vec![
Value::Map(
vec![
(
Value::String("width".to_owned()),
Value::Number(Number::new(20)),
),
(
Value::String("height".to_owned()),
Value::Number(Number::new(5)),
),
(
Value::String("name".to_owned()),
Value::String("The Room".to_owned()),
),
]
.into_iter()
.collect(),
),
Value::Map(
vec![
(
Value::String("width".to_owned()),
Value::Number(Number::new(10.0)),
),
(
Value::String("height".to_owned()),
Value::Number(Number::new(10.0)),
),
(
Value::String("name".to_owned()),
Value::String("Another room".to_owned()),
),
(
Value::String("enemy_levels".to_owned()),
Value::Map(
vec![
(
Value::String("Enemy1".to_owned()),
Value::Number(Number::new(3)),
),
(
Value::String("Enemy2".to_owned()),
Value::Number(Number::new(5)),
),
(
Value::String("Enemy3".to_owned()),
Value::Number(Number::new(7)),
),
]
.into_iter()
.collect(),
),
),
]
.into_iter()
.collect(),
),
]))))
);
}
}