add serde de/ser impls for error

Signed-off-by: Jason Volk <jason@zemos.net>

src/core/error/mod.rs

@@ -2,6 +2,7 @@ mod err;
 mod log;
 mod panic;
 mod response;
+mod serde;
 
 use std::{any::Any, borrow::Cow, convert::Infallible, fmt};
 
@@ -56,6 +57,10 @@ pub enum Error {
 	Regex(#[from] regex::Error),
 	#[error("Request error: {0}")]
 	Reqwest(#[from] reqwest::Error),
+	#[error("{0}")]
+	SerdeDe(Cow<'static, str>),
+	#[error("{0}")]
+	SerdeSer(Cow<'static, str>),
 	#[error(transparent)]
 	TomlDe(#[from] toml::de::Error),
 	#[error(transparent)]

src/core/error/serde.rs

@@ -0,0 +1,13 @@
+use std::fmt::Display;
+
+use serde::{de, ser};
+
+use crate::Error;
+
+impl de::Error for Error {
+	fn custom<T: Display + ToString>(msg: T) -> Self { Self::SerdeDe(msg.to_string().into()) }
+}
+
+impl ser::Error for Error {
+	fn custom<T: Display + ToString>(msg: T) -> Self { Self::SerdeSer(msg.to_string().into()) }
+}