Function open_repo_view_with 

pub fn open_repo_view_with(
    view: &str,
    mode_id: &str,
    rest: &str,
    store: &BufferStoreHandle,
    scopes: &RepoScopes,
    active: BufferId,
) -> Effect

MR.3: open_repo_view for a view that encodes parameters of its own — the commit family’s target (*magit:augment:<repo>:<sha>*) and, from MR.3b, the path- and revision-scoped views.

rest is the view’s own encoding, verbatim; this function only puts the repository in front of it.