Ethers MockResponse order

mock.rs

/// MockProvider seems to stack response in the wrong order
/// If I've a test that expect to:
///  - get_latest_block_number
///  - get_block
///
/// I'm expecting to define the mock for `get_last_block_number` and then `get_block`.
/// It's because of how MockProvider is processing request: https://github.com/gakonst/ethers-rs/blob/master/ethers-providers/src/rpc/transports/mock.rs#L64
/// When a request comes in, it pop_back instead of pop_front.
/// However, in the current setup I need to do the opposite, making the definition a bit weird in tests:


/// Test from: https://github.com/FuelLabs/fuel-canary-watchtower/blob/8d2939447a6495564b95f67d359b697695d11992/src/ethereum_watcher/ethereum_chain.rs#L130
/// Executing: https://github.com/FuelLabs/fuel-canary-watchtower/blob/8d2939447a6495564b95f67d359b697695d11992/src/ethereum_watcher/ethereum_chain.rs#L52
#[tokio::test]
async fn test_get_seconds_since_last_block() {
    let (mock, chain) = setup_mock_provider().await;
    let latest_block_number = U64::from(100);
    let past_timestamp = U256::from(SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_secs() - 10);

    mock.push_response(MockResponse::Value(
        serde_json::to_value(&Block::<()> {
            number: Some(latest_block_number),
            timestamp: past_timestamp,
            ..Default::default()
        })
        .unwrap(),
    ));

    mock.push_response(MockResponse::Value(serde_json::json!(latest_block_number)));

    let seconds_since_last_block = chain.get_seconds_since_last_block().await;
    assert!(seconds_since_last_block.is_ok());
    assert_eq!(seconds_since_last_block.unwrap(), 10);
}