1 files changed, 119 insertions, 0 deletions
diff --git a/vendor/gix/src/head/peel.rs b/vendor/gix/src/head/peel.rs
new file mode 100644
index 000000000..65a876bc4
--- /dev/null
+++ b/vendor/gix/src/head/peel.rs
@@ -0,0 +1,119 @@
+use crate::{
+    ext::{ObjectIdExt, ReferenceExt},
+    Head,
+};
+
+mod error {
+    use crate::{object, reference};
+
+    /// The error returned by [Head::peel_to_id_in_place()][super::Head::peel_to_id_in_place()] and [Head::into_fully_peeled_id()][super::Head::into_fully_peeled_id()].
+    #[derive(Debug, thiserror::Error)]
+    #[allow(missing_docs)]
+    pub enum Error {
+        #[error(transparent)]
+        FindExistingObject(#[from] object::find::existing::Error),
+        #[error(transparent)]
+        PeelReference(#[from] reference::peel::Error),
+    }
+}
+
+pub use error::Error;
+
+use crate::head::Kind;
+
+///
+pub mod to_commit {
+    use crate::object;
+
+    /// The error returned by [Head::peel_to_commit_in_place()][super::Head::peel_to_commit_in_place()].
+    #[derive(Debug, thiserror::Error)]
+    #[allow(missing_docs)]
+    pub enum Error {
+        #[error(transparent)]
+        Peel(#[from] super::Error),
+        #[error("Branch '{name}' does not have any commits")]
+        Unborn { name: gix_ref::FullName },
+        #[error(transparent)]
+        ObjectKind(#[from] object::try_into::Error),
+    }
+}
+
+impl<'repo> Head<'repo> {
+    // TODO: tests
+    /// Peel this instance to make obtaining its final target id possible, while returning an error on unborn heads.
+    pub fn peeled(mut self) -> Result<Self, Error> {
+        self.peel_to_id_in_place().transpose()?;
+        Ok(self)
+    }
+
+    // TODO: tests
+    /// Follow the symbolic reference of this head until its target object and peel it by following tag objects until there is no
+    /// more object to follow, and return that object id.
+    ///
+    /// Returns `None` if the head is unborn.
+    pub fn peel_to_id_in_place(&mut self) -> Option<Result<crate::Id<'repo>, Error>> {
+        Some(match &mut self.kind {
+            Kind::Unborn(_name) => return None,
+            Kind::Detached {
+                peeled: Some(peeled), ..
+            } => Ok((*peeled).attach(self.repo)),
+            Kind::Detached { peeled: None, target } => {
+                match target
+                    .attach(self.repo)
+                    .object()
+                    .map_err(Into::into)
+                    .and_then(|obj| obj.peel_tags_to_end().map_err(Into::into))
+                    .map(|peeled| peeled.id)
+                {
+                    Ok(peeled) => {
+                        self.kind = Kind::Detached {
+                            peeled: Some(peeled),
+                            target: *target,
+                        };
+                        Ok(peeled.attach(self.repo))
+                    }
+                    Err(err) => Err(err),
+                }
+            }
+            Kind::Symbolic(r) => {
+                let mut nr = r.clone().attach(self.repo);
+                let peeled = nr.peel_to_id_in_place().map_err(Into::into);
+                *r = nr.detach();
+                peeled
+            }
+        })
+    }
+
+    // TODO: tests
+    // TODO: something similar in `crate::Reference`
+    /// Follow the symbolic reference of this head until its target object and peel it by following tag objects until there is no
+    /// more object to follow, transform the id into a commit if possible and return that.
+    ///
+    /// Returns an error if the head is unborn or if it doesn't point to a commit.
+    pub fn peel_to_commit_in_place(&mut self) -> Result<crate::Commit<'repo>, to_commit::Error> {
+        let id = self.peel_to_id_in_place().ok_or_else(|| to_commit::Error::Unborn {
+            name: self.referent_name().expect("unborn").to_owned(),
+        })??;
+        id.object()
+            .map_err(|err| to_commit::Error::Peel(Error::FindExistingObject(err)))
+            .and_then(|object| object.try_into_commit().map_err(Into::into))
+    }
+
+    /// Consume this instance and transform it into the final object that it points to, or `None` if the `HEAD`
+    /// reference is yet to be born.
+    pub fn into_fully_peeled_id(self) -> Option<Result<crate::Id<'repo>, Error>> {
+        Some(match self.kind {
+            Kind::Unborn(_name) => return None,
+            Kind::Detached {
+                peeled: Some(peeled), ..
+            } => Ok(peeled.attach(self.repo)),
+            Kind::Detached { peeled: None, target } => target
+                .attach(self.repo)
+                .object()
+                .map_err(Into::into)
+                .and_then(|obj| obj.peel_tags_to_end().map_err(Into::into))
+                .map(|obj| obj.id.attach(self.repo)),
+            Kind::Symbolic(r) => r.attach(self.repo).peel_to_id_in_place().map_err(Into::into),
+        })
+    }
+}