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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use std::fmt::Display;
use error_support::{handle_error, ErrorHandling, GetErrorHandling};
#[derive(Debug, thiserror::Error)]
struct Error {}
impl Display for Error {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "Internal Error!")
}
}
#[derive(Debug, thiserror::Error)]
struct ExternalError {}
impl Display for ExternalError {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "External Error!")
}
}
impl GetErrorHandling for Error {
type ExternalError = ExternalError;
fn get_error_handling(&self) -> error_support::ErrorHandling<Self::ExternalError> {
ErrorHandling::convert(ExternalError {})
}
}
#[handle_error(Error)] // Works.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error("Error")] // Quoted string instead of a path
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error(2)] // bad type.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error] // No args.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error()] // empty args.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error(A, B)] // too many args.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
#[handle_error(Key="Value")] // unknown args.
fn func() -> ::std::result::Result<String, ExternalError> {
Err(Error{})
}
// When the "external" error doesn't implement `std::error::Error` (eg, we use String) but the
// "inner" one does.
#[derive(Debug, thiserror::Error)]
struct Error2 {
string: String,
}
impl Display for Error2 {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "String Error!")
}
}
impl GetErrorHandling for Error2 {
type ExternalError = String;
fn get_error_handling(&self) -> error_support::ErrorHandling<Self::ExternalError> {
ErrorHandling::convert(self.string.clone())
}
}
#[handle_error(Error2)] // Must implement `std::error::Error`
fn func_error_to_string() -> Result<String, String> {
Err(Error2 { string: "oops!".into() })
}
// When the "external" error does implement `std::error::Error` but the
// "inner" one does not.
#[derive(Debug, thiserror::Error)]
struct ExternalError2 {}
impl Display for ExternalError2 {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "External Error")
}
}
// So we can't even try to `impl GetErrorHandling for String` as String isn't
// in this crate!
// So the output complains about *both* that trait missing *and* the lack of `std::error::Error`
#[handle_error(String)] // Must implement `std::error::Error`
fn func_string_to_error() -> Result<String, ExternalError2> {
Err("oops!".into())
}
fn main(){}