use gix_object::compute_hash in a test and benchmark

Author: emilazy

gix-object/benches/edit_tree.rs

@@ -144,11 +144,7 @@ fn new_inmemory_writes() -> (TreeStore, impl FnMut(&Tree) -> Result<ObjectId, st
         move |tree: &Tree| {
             buf.clear();
             tree.write_to(&mut buf)?;
-            let header = gix_object::encode::loose_header(gix_object::Kind::Tree, buf.len() as u64);
-            let mut hasher = gix_features::hash::hasher(gix_hash::Kind::Sha1);
-            hasher.update(&header);
-            hasher.update(&buf);
-            let id = hasher.digest().into();
+            let id = gix_object::compute_hash(gix_hash::Kind::Sha1, gix_object::Kind::Tree, &buf);
             let mut borrowed = store.borrow_mut();
             match borrowed.entry(id) {
                 Entry::Occupied(_) => {}

gix-object/tests/object/tree/editor.rs

@@ -805,11 +805,7 @@ mod utils {
             move |tree: &Tree| {
                 buf.clear();
                 tree.write_to(&mut buf)?;
-                let header = gix_object::encode::loose_header(gix_object::Kind::Tree, buf.len() as u64);
-                let mut hasher = gix_features::hash::hasher(gix_hash::Kind::Sha1);
-                hasher.update(&header);
-                hasher.update(&buf);
-                let id = hasher.digest().into();
+                let id = gix_object::compute_hash(gix_hash::Kind::Sha1, gix_object::Kind::Tree, &buf);
                 store.borrow_mut().insert(id, tree.clone());
                 let old = num_writes.get();
                 num_writes.set(old + 1);