Function build_pack_for_push 

pub fn build_pack_for_push(
    odb: &Odb,
    wants: &[ObjectId],
    haves: &[ObjectId],
    opts: &PackBuildOptions,
) -> Result<Vec<u8>>

Like build_pack, but uses HaveBoundary::TipsOnly for send-pack pushes.

Negotiated have tips bound the want-side walk lazily instead of pre-walking their full commit closure before enumeration. Collects write_pack_for_push into memory; pushes stream with that instead.

Errors

Same as build_pack: missing wants, corrupt objects, or pack write failures.