diff --git a/tests/test_transparent.rs b/tests/test_transparent.rs new file mode 100644 index 0000000..8fba5fe --- /dev/null +++ b/tests/test_transparent.rs @@ -0,0 +1,57 @@ +use anyhow::anyhow; +use std::error::Error as _; +use std::io; +use thiserror::Error; + +#[test] +fn test_transparent_struct() { + #[derive(Error, Debug)] + #[error(transparent)] + struct Error(ErrorKind); + + #[derive(Error, Debug)] + enum ErrorKind { + #[error("E0")] + E0, + #[error("E1")] + E1(#[from] io::Error), + } + + let error = Error(ErrorKind::E0); + assert_eq!("E0", error.to_string()); + assert!(error.source().is_none()); + + let io = io::Error::new(io::ErrorKind::Other, "oh no!"); + let error = Error(ErrorKind::from(io)); + assert_eq!("E1", error.to_string()); + error.source().unwrap().downcast_ref::().unwrap(); +} + +#[test] +fn test_transparent_enum() { + #[derive(Error, Debug)] + enum Error { + #[error("this failed")] + This, + #[error(transparent)] + Other(anyhow::Error), + } + + let error = Error::This; + assert_eq!("this failed", error.to_string()); + + let error = Error::Other(anyhow!("inner").context("outer")); + assert_eq!("outer", error.to_string()); + assert_eq!("inner", error.source().unwrap().to_string()); +} + +#[test] +fn test_anyhow() { + #[derive(Error, Debug)] + #[error(transparent)] + struct Any(#[from] anyhow::Error); + + let error = Any::from(anyhow!("inner").context("outer")); + assert_eq!("outer", error.to_string()); + assert_eq!("inner", error.source().unwrap().to_string()); +}