Function validate_source_links 

pub fn validate_source_links<'a>(
    entries: impl IntoIterator<Item = (&'a str, Option<&'a str>)>,
) -> Result<(), String>

Validate portable Git link targets against a complete, filtered tree without accessing the host. Missing targets and cycles are retained, as they are in Git. A manifest entry may never be another entry’s parent: materialization must not write through a symlink.

Errors

Returns an error for an escaping, nonportable, or overlong target, or overlapping entries.