feat: filter::Pipeline::worktree_file_to_object() now can add `Comm…

…it` type objects.

gix/tests/fixtures/repo_with_untracked_files.sh

@@ -1,9 +1,16 @@
 #!/usr/bin/env bash
 set -eu -o pipefail
 
+git init embedded-repository
+(cd embedded-repository
+  echo content >file && git add file && git commit -m "init"
+)
+
 git init -q
 echo content >file
 ln -s file link
 
 echo binary >exe && chmod +x exe
 mkfifo fifo
+
+git submodule add ./embedded-repository submodule

gix/tests/gix/repository/filter.rs

@@ -40,6 +40,15 @@ fn pipeline_worktree_file_to_object() -> crate::Result {
         t.map(|t| (t.0, t.1))
     }
 
+    let submodule_id = hex_to_id("a047f8183ba2bb7eb00ef89e60050c5fde740483");
+    assert_eq!(
+        take_two(pipe.worktree_file_to_object("embedded-repository".into(), &index)?),
+        Some((submodule_id, gix::object::tree::EntryKind::Commit))
+    );
+    assert_eq!(
+        take_two(pipe.worktree_file_to_object("submodule".into(), &index)?),
+        Some((submodule_id, gix::object::tree::EntryKind::Commit))
+    );
     assert_eq!(
         take_two(pipe.worktree_file_to_object("file".into(), &index)?),
         Some((