fix: remove ambiguity between options and results trait methods

1. Remove the conditional trait methods `context` and `with_context`
   from `WrapErr`
2. Remove ambiguity between "wrapping errors" with another, and
   converting a `None` value to an error.

The anyhow compatibility methods (`context` and `with_context`) were
introduced as conditional required methods for the trait `WrapErr`, as
well as another separate trait `ContextCompat`, implemented for options
*and* results.

The latter trait also provided methods `wrap_err` and `wrap_err_with`.
This led to confusion as the two distinct trait had the same methods,
except one was implemented on results, and one of options and results.

Further, this did not align with our error model, wherein errors are
wrapped with other errors in a chain now that options (which are no
errors and have no message) could be "wrapped"

See: #149

eyre/src/context.rs

@@ -61,42 +61,34 @@ where
  Err(e) => Err(e.ext_report(msg())),
  }
  }
+}
 
- #[cfg(feature = "anyhow")]
- fn context<D>(self, msg: D) -> Result<T, Report>
+#[cfg(feature = "anyhow")]
+impl<T, E> crate::ContextCompat<T> for Result<T, E>
+where
+ Self: WrapErr<T, E>,
+{
+ #[track_caller]
+ fn context<D>(self, msg: D) -> crate::Result<T, Report>
  where
  D: Display + Send + Sync + 'static,
  {
  self.wrap_err(msg)
  }
 
- #[cfg(feature = "anyhow")]
- fn with_context<D, F>(self, msg: F) -> Result<T, Report>
+ #[track_caller]
+ fn with_context<D, F>(self, f: F) -> crate::Result<T, Report>
  where
  D: Display + Send + Sync + 'static,
  F: FnOnce() -> D,
  {
- self.wrap_err_with(msg)
+ self.wrap_err_with(f)
  }
 }
 
 #[cfg(feature = "anyhow")]
 impl<T> crate::ContextCompat<T> for Option<T> {
- fn wrap_err<D>(self, msg: D) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static,
- {
- self.context(msg)
- }
-
- fn wrap_err_with<D, F>(self, msg: F) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static,
- F: FnOnce() -> D,
- {
- self.with_context(msg)
- }
-
+ #[track_caller]
  fn context<D>(self, msg: D) -> Result<T, Report>
  where
  D: Display + Send + Sync + 'static,
@@ -107,6 +99,7 @@ impl<T> crate::ContextCompat<T> for Option<T> {
  }
  }
 
+ #[track_caller]
  fn with_context<D, F>(self, msg: F) -> Result<T, Report>
  where
  D: Display + Send + Sync + 'static,

eyre/src/lib.rs

@@ -1125,21 +1125,6 @@ pub trait WrapErr<T, E>: context::private::Sealed {
  where
  D: Display + Send + Sync + 'static,
  F: FnOnce() -> D;
-
- /// Compatibility re-export of wrap_err for interop with `anyhow`
- #[cfg(feature = "anyhow")]
- #[cfg_attr(track_caller, track_caller)]
- fn context<D>(self, msg: D) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static;
-
- /// Compatibility re-export of wrap_err_with for interop with `anyhow`
- #[cfg(feature = "anyhow")]
- #[cfg_attr(track_caller, track_caller)]
- fn with_context<D, F>(self, f: F) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static,
- F: FnOnce() -> D;
 }
 
 /// Provides the [`ok_or_eyre`][OptionExt::ok_or_eyre] method for [`Option`].
@@ -1197,7 +1182,8 @@ pub trait OptionExt<T>: context::private::Sealed {
  M: Debug + Display + Send + Sync + 'static;
 }
 
-/// Provides the `context` method for `Option` when porting from `anyhow`
+/// Provides the `context` and `with_context` methods for `Result` and `Option` to enhance
+/// compatibility when porting from anyhow.
 ///
 /// This trait is sealed and cannot be implemented for types outside of
 /// `eyre`.
@@ -1256,19 +1242,6 @@ pub trait ContextCompat<T>: context::private::Sealed {
  where
  D: Display + Send + Sync + 'static,
  F: FnOnce() -> D;
-
- /// Compatibility re-export of `context` for porting from `anyhow` to `eyre`
- #[cfg_attr(track_caller, track_caller)]
- fn wrap_err<D>(self, msg: D) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static;
-
- /// Compatibility re-export of `with_context` for porting from `anyhow` to `eyre`
- #[cfg_attr(track_caller, track_caller)]
- fn wrap_err_with<D, F>(self, f: F) -> Result<T, Report>
- where
- D: Display + Send + Sync + 'static,
- F: FnOnce() -> D;
 }
 
 /// Equivalent to Ok::<_, eyre::Error>(value).

eyre/tests/test_location.rs

@@ -101,6 +101,8 @@ fn test_option_ok_or_eyre() {
 #[cfg(feature = "anyhow")]
 #[test]
 fn test_context() {
+ use eyre::ContextCompat;
+
  let _ = eyre::set_hook(Box::new(|_e| {
  let expected_location = file!();
  Box::new(LocationHandler::new(expected_location))
@@ -117,6 +119,8 @@ fn test_context() {
 #[cfg(feature = "anyhow")]
 #[test]
 fn test_with_context() {
+ use eyre::ContextCompat;
+
  let _ = eyre::set_hook(Box::new(|_e| {
  let expected_location = file!();
  Box::new(LocationHandler::new(expected_location))
@@ -139,7 +143,7 @@ fn test_option_compat_wrap_err() {
  }));
 
  use eyre::ContextCompat;
- let err = None::<()>.wrap_err("oopsie").unwrap_err();
+ let err = None::<()>.context("oopsie").unwrap_err();
 
  // should panic if the location isn't in our crate
  println!("{:?}", err);
@@ -154,7 +158,7 @@ fn test_option_compat_wrap_err_with() {
  }));
 
  use eyre::ContextCompat;
- let err = None::<()>.wrap_err_with(|| "oopsie").unwrap_err();
+ let err = None::<()>.with_context(|| "oopsie").unwrap_err();
 
  // should panic if the location isn't in our crate
  println!("{:?}", err);