Function hook_lock_directory 

pub fn hook_lock_directory(common_directory: &Path) -> PathBuf

What: The hook lock directory under the common Git directory. Why: The incumbent’s join(commonDir, 'cli-git', 'hook.lock'); the same lock serializes both wrappers.

In TS you’d write (pseudocode):

join(commonDir, 'cli-git', 'hook.lock')