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|
use super::*;
use core::{
num::ParseIntError,
str::{FromStr, ParseBoolError},
};
use pretty_assertions::assert_eq;
use serde_with::DeserializeFromStr;
#[derive(Debug, PartialEq, DeserializeFromStr)]
struct A {
a: u32,
b: bool,
}
impl FromStr for A {
type Err = String;
/// Parse a value like `123<>true`
fn from_str(s: &str) -> Result<Self, Self::Err> {
let mut parts = s.split("<>");
let number = parts
.next()
.ok_or_else(|| "Missing first value".to_string())?
.parse()
.map_err(|err: ParseIntError| err.to_string())?;
let bool = parts
.next()
.ok_or_else(|| "Missing second value".to_string())?
.parse()
.map_err(|err: ParseBoolError| err.to_string())?;
Ok(Self { a: number, b: bool })
}
}
#[test]
fn test_deserialize_fromstr() {
check_deserialization(A { a: 159, b: true }, "\"159<>true\"");
check_deserialization(A { a: 999, b: false }, "\"999<>false\"");
check_deserialization(A { a: 0, b: true }, "\"0<>true\"");
}
#[test]
fn test_deserialize_from_bytes() {
use serde::de::{value::Error, Deserialize, Deserializer, Visitor};
// Unfortunately serde_json is too clever (i.e. handles bytes gracefully)
// so instead create a custom deserializer which can only deserialize bytes.
// All other deserialize_* fns are forwarded to deserialize_bytes
struct ByteDeserializer(&'static [u8]);
impl<'de> Deserializer<'de> for ByteDeserializer {
type Error = Error;
fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
where
V: Visitor<'de>,
{
self.deserialize_bytes(visitor)
}
fn deserialize_bytes<V>(self, visitor: V) -> Result<V::Value, Self::Error>
where
V: Visitor<'de>,
{
visitor.visit_bytes(self.0)
}
serde::forward_to_deserialize_any! {
bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string
byte_buf option unit unit_struct newtype_struct seq tuple
tuple_struct map struct enum identifier ignored_any
}
}
// callstack: A::deserialize -> deserialize_str -> deserialize_any ->
// deserialize_bytes -> visit_bytes -> visit_str -> success!
let a = A::deserialize(ByteDeserializer(b"159<>true")).unwrap();
assert_eq!(A { a: 159, b: true }, a);
}
#[test]
fn test_deserialize_fromstr_in_vec() {
check_deserialization(
vec![
A { a: 123, b: false },
A { a: 0, b: true },
A { a: 999, b: true },
],
r#"[
"123<>false",
"0<>true",
"999<>true"
]"#,
);
}
|
