Function settled_entry 

pub fn settled_entry(
    context: &GitContext,
    cwd: &Path,
    index: &Path,
    path: &[u8],
) -> Result<Option<(String, String)>, GitFailure>

What: The settled mode and object of one path in the private index, or nothing when it has no stage-zero entry. Why: A correction counts only while the settled entry still has the ordinary mode of the original.

In TS you’d write (pseudocode):

(await loadIndexEntries({ gitPath, cwd, indexPath, paths })).get(path)