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use serde;
use std::str::FromStr;
use std::fmt;
use super::pure_decimal::Decimal;
#[cfg(feature = "serde")]
impl serde::ser::Serialize for Decimal {
fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
where
S: serde::ser::Serializer,
{
serializer.serialize_str(&self.0.to_string())
}
}
#[cfg(feature = "serde")]
impl<'de> serde::de::Deserialize<'de> for Decimal {
fn deserialize<D>(deserializer: D) -> Result<Decimal, D::Error>
where
D: serde::de::Deserializer<'de>,
{
deserializer.deserialize_any(SerdeDecimalVisitor)
}
}
#[cfg(feature = "serde")]
#[allow(non_camel_case_types)]
struct SerdeDecimalVisitor;
#[cfg(feature = "serde")]
impl<'de> serde::de::Visitor<'de> for SerdeDecimalVisitor {
type Value = Decimal;
fn expecting(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "a Decimal value")
}
fn visit_str<E>(self, s: &str) -> Result<Decimal, E>
where
E: serde::de::Error,
{
use serde::de::Unexpected;
Decimal::from_str(s).map_err(|_| E::invalid_value(Unexpected::Str(s), &self))
}
fn visit_f64<E>(self, value: f64) -> Result<Decimal, E>
where
E: serde::de::Error,
{
use serde::de::Unexpected;
Decimal::from_str(&value.to_string()).map_err(|_| E::invalid_value(Unexpected::Float(value), &self))
}
fn visit_i64<E>(self, value: i64) -> Result<Decimal, E>
where
E: serde::de::Error,
{
Ok(Decimal::from(value))
}
fn visit_u64<E>(self, value: u64) -> Result<Decimal, E>
where
E: serde::de::Error,
{
Ok(Decimal::from(value))
}
}
#[cfg(test)]
mod tests {
extern crate serde_json;
use super::*;
#[derive(Serialize, Deserialize, Debug)]
struct Record {
amount: Decimal,
}
#[test]
fn deserialize_valid_decimal() {
let data = [
("{\"amount\":\"1.234\"}", "1.234"),
("{\"amount\":1234}", "1234"),
("{\"amount\":1234.56}", "1234.56"),
];
for &(serialized, value) in data.iter() {
let result = serde_json::from_str(serialized);
assert_eq!(
true,
result.is_ok(),
"expected successful deserialization for {}. Error: {:?}",
serialized,
result.err().unwrap()
);
let record: Record = result.unwrap();
assert_eq!(
value,
record.amount.to_string(),
"expected: {}, actual: {}",
value,
record.amount.to_string()
);
}
}
#[test]
#[should_panic]
fn deserialize_invalid_decimal() {
let serialized = "{\"amount\":\"foo\"}";
let _: Record = serde_json::from_str(serialized).unwrap();
}
#[test]
fn serialize_decimal() {
let record = Record { amount: dec!(1.234) };
let serialized = serde_json::to_string(&record).unwrap();
assert_eq!("{\"amount\":\"1.234\"}", serialized);
}
}