resplus_impl/
lib.rs

1#[cfg(feature = "async")]
2mod fut;
3#[cfg(feature = "async")]
4pub use fut::FutResultChain;
5mod sync;
6use std::{borrow::Cow, fmt::Display};
7pub use sync::ResultChain;
8
9#[derive(Debug)]
10pub struct ErrorChain<I> {
11    pub source: I,
12    context: Vec<Cow<'static, str>>,
13}
14
15impl<I> ErrorChain<I> {
16    pub fn new(source: impl Into<I>) -> Self {
17        Self {
18            source: source.into(),
19            context: Vec::new(),
20        }
21    }
22}
23
24impl<I: Display> Display for ErrorChain<I> {
25    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
26        write!(f, "source: {}", self.source)?;
27        for c in &self.context {
28            write!(f, "\n  {}", c)?;
29        }
30        Ok(())
31    }
32}
33
34#[macro_export]
35macro_rules! define_error {
36    ($error:ty, $source:ty$(, $t:ty)*) => {
37        impl From<$source> for ErrorChain {
38            fn from(value: $source) -> Self {
39                ErrorChain(resplus::ErrorChain::new(value))
40            }
41        }
42        define_error!($error$(, $t)*);
43    };
44    ($error:ty) => {
45        impl From<$error> for ErrorChain {
46            fn from(value: $error) -> Self {
47                ErrorChain(resplus::ErrorChain::new(value))
48            }
49        }
50
51        impl From<resplus::ErrorChain<$error>> for ErrorChain {
52            fn from(value: resplus::ErrorChain<$error>) -> Self {
53                ErrorChain(value)
54            }
55        }
56
57        #[derive(Debug)]
58        pub struct ErrorChain(resplus::ErrorChain<$error>);
59
60        impl std::fmt::Display for ErrorChain {
61            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
62                write!(f, "{}", self.0)
63            }
64        }
65
66        impl std::error::Error for ErrorChain {}
67    };
68}
69
70#[cfg(test)]
71mod tests {
72    macro_rules! about {
73        ($e:expr) => {
74            ($e).about("source")
75        };
76    }
77    pub(crate) use about;
78    macro_rules! about_else {
79        ($e:expr) => {
80            ($e).about_else(|| "source")
81        };
82    }
83    pub(crate) use about_else;
84}
resplus_impl/lib.rs

resplus_impl/
lib.rs
