on failed: src.len() == dst.len()assertion failed: edge.height == self.node.height - 1assertion failed: old_right_len + count <= CAPACITYassertion failed: old_left_len >= countinternal error: entered unreachable codeassertion failed: old_left_len + count <= CAPACITYassertion failed: old_right_len >= countassertion failed: match track_edge_idx {
    LeftOrRight::Left(idx) => idx <= old_left_len,
    LeftOrRight::Right(idx) => idx <= right_len,
}assertion failed: new_left_len <= CAPACITY