feat: add Repository::find_*() methods for every object type.

Author: Byron

gix/src/object/errors.rs

@@ -29,6 +29,19 @@ pub mod find {
     pub mod existing {
         /// An object could not be found in the database, or an error occurred when trying to obtain it.
         pub type Error = gix_object::find::existing::Error;
+        ///
+        #[allow(clippy::empty_docs)]
+        pub mod with_conversion {
+            /// The error returned by [Repository::find_commit()](crate::Repository::find_commit).
+            #[derive(Debug, thiserror::Error)]
+            #[allow(missing_docs)]
+            pub enum Error {
+                #[error(transparent)]
+                Find(#[from] crate::object::find::existing::Error),
+                #[error(transparent)]
+                Convert(#[from] crate::object::try_into::Error),
+            }
+        }
     }
 }
 

gix/src/repository/object.rs

@@ -10,7 +10,7 @@ use gix_ref::{
 };
 use smallvec::SmallVec;
 
-use crate::{commit, ext::ObjectIdExt, object, tag, Blob, Id, Object, Reference, Tree};
+use crate::{commit, ext::ObjectIdExt, object, tag, Blob, Commit, Id, Object, Reference, Tag, Tree};
 
 /// Methods related to object creation.
 impl crate::Repository {
@@ -38,6 +38,35 @@ impl crate::Repository {
         Ok(Object::from_data(id, kind, buf, self))
     }
 
+    /// Find a commit with `id` or fail if there was no object or the object wasn't a commit.
+    pub fn find_commit(
+        &self,
+        id: impl Into<ObjectId>,
+    ) -> Result<Commit<'_>, object::find::existing::with_conversion::Error> {
+        Ok(self.find_object(id)?.try_into_commit()?)
+    }
+
+    /// Find a tree with `id` or fail if there was no object or the object wasn't a tree.
+    pub fn find_tree(
+        &self,
+        id: impl Into<ObjectId>,
+    ) -> Result<Tree<'_>, object::find::existing::with_conversion::Error> {
+        Ok(self.find_object(id)?.try_into_tree()?)
+    }
+
+    /// Find an annotated tag with `id` or fail if there was no object or the object wasn't a tag.
+    pub fn find_tag(&self, id: impl Into<ObjectId>) -> Result<Tag<'_>, object::find::existing::with_conversion::Error> {
+        Ok(self.find_object(id)?.try_into_tag()?)
+    }
+
+    /// Find a blob with `id` or fail if there was no object or the object wasn't a blob.
+    pub fn find_blob(
+        &self,
+        id: impl Into<ObjectId>,
+    ) -> Result<Blob<'_>, object::find::existing::with_conversion::Error> {
+        Ok(self.find_object(id)?.try_into_blob()?)
+    }
+
     /// Obtain information about an object without fully decoding it, or fail if the object doesn't exist.
     ///
     /// Note that despite being cheaper than [`Self::find_object()`], there is still some effort traversing delta-chains.