fix!: improve error messages when failing to find references.

It's breaking due to changes in the error type.

Author: Byron

gix/src/reference/errors.rs

@@ -110,14 +110,16 @@ pub mod head_tree_id {
 pub mod find {
     ///
     pub mod existing {
+        use gix_ref::PartialName;
+
         /// The error returned by [`find_reference(…)`][crate::Repository::find_reference()], and others.
         #[derive(Debug, thiserror::Error)]
         #[allow(missing_docs)]
         pub enum Error {
             #[error(transparent)]
             Find(#[from] crate::reference::find::Error),
-            #[error("The reference did not exist")]
-            NotFound,
+            #[error("The reference '{}' did not exist", name.as_ref().as_bstr())]
+            NotFound { name: PartialName },
         }
     }
 
@@ -127,7 +129,5 @@ pub mod find {
     pub enum Error {
         #[error(transparent)]
         Find(#[from] gix_ref::file::find::Error),
-        #[error(transparent)]
-        PackedRefsOpen(#[from] gix_ref::packed::buffer::open::Error),
     }
 }

gix/src/repository/reference.rs

@@ -159,7 +159,7 @@ impl crate::Repository {
         Ok(match head.inner.target {
             Target::Symbolic(branch) => match self.find_reference(&branch) {
                 Ok(r) => crate::head::Kind::Symbolic(r.detach()),
-                Err(reference::find::existing::Error::NotFound) => crate::head::Kind::Unborn(branch),
+                Err(reference::find::existing::Error::NotFound { .. }) => crate::head::Kind::Unborn(branch),
                 Err(err) => return Err(err),
             },
             Target::Object(target) => crate::head::Kind::Detached {
@@ -222,11 +222,19 @@ impl crate::Repository {
     /// without that being considered an error.
     pub fn find_reference<'a, Name, E>(&self, name: Name) -> Result<Reference<'_>, reference::find::existing::Error>
     where
-        Name: TryInto<&'a PartialNameRef, Error = E>,
+        Name: TryInto<&'a PartialNameRef, Error = E> + Clone,
         gix_ref::file::find::Error: From<E>,
     {
+        // TODO: is there a way to just pass `partial_name` to `try_find_reference()`? Compiler freaks out then
+        //       as it still wants to see `E` there, not `Infallible`.
+        let partial_name = name
+            .clone()
+            .try_into()
+            .map_err(|err| reference::find::Error::Find(gix_ref::file::find::Error::from(err)))?;
         self.try_find_reference(name)?
-            .ok_or(reference::find::existing::Error::NotFound)
+            .ok_or_else(|| reference::find::existing::Error::NotFound {
+                name: partial_name.to_owned(),
+            })
     }
 
     /// Return a platform for iterating references.
@@ -249,8 +257,7 @@ impl crate::Repository {
         Name: TryInto<&'a PartialNameRef, Error = E>,
         gix_ref::file::find::Error: From<E>,
     {
-        let state = self;
-        match state.refs.try_find(name) {
+        match self.refs.try_find(name) {
             Ok(r) => match r {
                 Some(r) => Ok(Some(Reference::from_ref(r, self))),
                 None => Ok(None),