pub fn mock_process_instruction(
    loader_id: &Pubkey,
    program_indices: Vec<usize>,
    instruction_data: &[u8],
    transaction_accounts: Vec<TransactionAccount>,
    instruction_accounts: Vec<AccountMeta>,
    expected_result: Result<(), InstructionError>,
    process_instruction: ProcessInstructionWithContext
) -> Vec<AccountSharedData>Notable traits for Vec<u8, A>impl<A> Write for Vec<u8, A> where
    A: Allocator