Function parse_tree_with_oid_len 

pub fn parse_tree_with_oid_len(
    data: &[u8],
    oid_len: usize,
) -> Result<Vec<TreeEntry>>

Parse a tree blob assuming a fixed raw OID width (oid_len bytes).

Returns an error if the data does not parse cleanly into whole entries of that width (used by parse_tree to detect the hash algorithm).