Function pattern_idx_matching_relative_path

pub fn pattern_idx_matching_relative_path(
    list: &List<Ignore>,
    relative_path: &BStr,
    basename_pos: Option<usize>,
    is_dir: Option<bool>,
    case: Case,
) -> Option<usize>

Like pattern_matching_relative_path(), but returns an index to the pattern that matched relative_path, instead of the match itself.