70 lines
1.5 KiB
Rust
70 lines
1.5 KiB
Rust
use core::fmt;
|
|
use core::marker::PhantomData;
|
|
use core::str::{self, FromStr};
|
|
use serde::de;
|
|
|
|
/// A serde visitor that works for `T`s implementing `FromStr`.
|
|
pub struct FromStrVisitor<T> {
|
|
expectation: &'static str,
|
|
_pd: PhantomData<T>,
|
|
}
|
|
|
|
impl<T> FromStrVisitor<T> {
|
|
pub fn new(expectation: &'static str) -> Self {
|
|
FromStrVisitor {
|
|
expectation,
|
|
_pd: PhantomData,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'de, T> de::Visitor<'de> for FromStrVisitor<T>
|
|
where
|
|
T: FromStr,
|
|
<T as FromStr>::Err: fmt::Display,
|
|
{
|
|
type Value = T;
|
|
|
|
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
|
|
formatter.write_str(self.expectation)
|
|
}
|
|
|
|
fn visit_str<E: de::Error>(self, v: &str) -> Result<Self::Value, E> {
|
|
FromStr::from_str(v).map_err(E::custom)
|
|
}
|
|
}
|
|
|
|
pub struct BytesVisitor<F> {
|
|
expectation: &'static str,
|
|
parse_fn: F,
|
|
}
|
|
|
|
impl<F, T, Err> BytesVisitor<F>
|
|
where
|
|
F: FnOnce(&[u8]) -> Result<T, Err>,
|
|
Err: fmt::Display,
|
|
{
|
|
pub fn new(expectation: &'static str, parse_fn: F) -> Self {
|
|
BytesVisitor {
|
|
expectation,
|
|
parse_fn,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'de, F, T, Err> de::Visitor<'de> for BytesVisitor<F>
|
|
where
|
|
F: FnOnce(&[u8]) -> Result<T, Err>,
|
|
Err: fmt::Display,
|
|
{
|
|
type Value = T;
|
|
|
|
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
|
|
formatter.write_str(self.expectation)
|
|
}
|
|
|
|
fn visit_bytes<E: de::Error>(self, v: &[u8]) -> Result<Self::Value, E> {
|
|
(self.parse_fn)(v).map_err(E::custom)
|
|
}
|
|
}
|