clonable_error/
lib.rs

1// Copyright 2019 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use anyhow::Error;
6use std::fmt;
7use std::sync::Arc;
8use thiserror::Error;
9
10/// A wrapper for `Error` that implements `Clone`.
11#[derive(Clone, Error)]
12pub struct ClonableError {
13    #[source]
14    err: Arc<Error>,
15}
16
17impl From<Error> for ClonableError {
18    fn from(err: Error) -> Self {
19        Self { err: Arc::new(err) }
20    }
21}
22
23impl fmt::Display for ClonableError {
24    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
25        self.err.fmt(f)
26    }
27}
28
29impl fmt::Debug for ClonableError {
30    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
31        self.err.fmt(f)
32    }
33}
34
35#[cfg(test)]
36mod tests {
37    use super::*;
38    use anyhow::format_err;
39    use thiserror::Error;
40
41    #[derive(Debug, Error, Clone)]
42    #[error("\"{}\" happened: {}", msg, cause)]
43    struct FooError {
44        msg: String,
45        #[source]
46        cause: ClonableError,
47    }
48
49    #[test]
50    fn clone() {
51        let cause = format_err!("root cause").into();
52        let err = FooError { msg: "something bad happened".to_string(), cause };
53        let cloned_err = err.clone();
54        assert_eq!(format!("{:?}", err), format!("{:?}", cloned_err));
55    }
56}
clonable_error/lib.rs

clonable_error/
lib.rs
