adjust to changes in git-protocol (#450)

Author: Byron

gitoxide-core/src/pack/receive.rs

@@ -319,6 +319,10 @@ fn write_raw_refs(refs: &[Ref], directory: PathBuf) -> std::io::Result<()> {
     };
     for r in refs {
         let (path, content) = match r {
+            Ref::Unborn { target } => (
+                assure_dir_exists(&"HEAD".to_owned().into())?,
+                format!("unborn HEAD: {}", target),
+            ),
             Ref::Symbolic {
                 full_ref_name: path,
                 target,

gitoxide-core/src/repository/remote.rs

@@ -216,6 +216,10 @@ mod refs_impl {
             path: String,
             object: String,
         },
+        Unborn {
+            path: String,
+            target: String,
+        },
         Symbolic {
             path: String,
             target: String,
@@ -226,6 +230,10 @@ mod refs_impl {
     impl From<fetch::Ref> for JsonRef {
         fn from(value: fetch::Ref) -> Self {
             match value {
+                fetch::Ref::Unborn { target } => JsonRef::Unborn {
+                    path: "HEAD".into(),
+                    target: target.to_string(),
+                },
                 fetch::Ref::Direct {
                     full_ref_name: path,
                     object,
@@ -271,6 +279,10 @@ mod refs_impl {
                 target,
                 object,
             } => write!(&mut out, "{} {} symref-target:{}", object, path, target).map(|_| object.as_ref()),
+            fetch::Ref::Unborn { target } => {
+                static NULL: git::hash::ObjectId = git::hash::ObjectId::null(git::hash::Kind::Sha1);
+                write!(&mut out, "unborn HEAD symref-target:{}", target).map(|_| NULL.as_ref())
+            }
         }
     }