Added Tests to BlockRangeScanner (#59)

Co-authored-by: Nenad <[email protected]>

Author: LeoPatOZ

src/block_range_scanner.rs

@@ -733,13 +733,147 @@ impl BlockRangeScannerClient {
 
 #[cfg(test)]
 mod tests {
-    use alloy::network::Ethereum;
+    use alloy::{
+        eips::BlockNumberOrTag,
+        network::Ethereum,
+        primitives::{B256, keccak256},
+        rpc::{
+            client::RpcClient,
+            types::{Block as RpcBlock, Header, Transaction},
+        },
+        transports::mock::Asserter,
+    };
     use alloy_node_bindings::Anvil;
-
+    use serde_json::{Value, json};
+    use tokio::sync::mpsc;
     use tokio_stream::StreamExt;
 
     use super::*;
 
+    fn test_config() -> Config {
+        Config { blocks_read_per_epoch: 5, reorg_rewind_depth: 5, block_confirmations: 0 }
+    }
+
+    fn mocked_provider(asserter: Asserter) -> RootProvider<Ethereum> {
+        RootProvider::new(RpcClient::mocked(asserter))
+    }
+
+    fn mock_block(number: u64, hash: B256) -> RpcBlock<Transaction, Header> {
+        let mut block: RpcBlock<Transaction, Header> = RpcBlock::default();
+        block.header.hash = hash;
+        block.header.number = number;
+        block
+    }
+
+    #[test]
+    fn block_range_scanner_defaults_match_constants() {
+        let scanner = BlockRangeScanner::new();
+
+        assert_eq!(scanner.blocks_read_per_epoch, DEFAULT_BLOCKS_READ_PER_EPOCH);
+        assert_eq!(scanner.reorg_rewind_depth, DEFAULT_REORG_REWIND_DEPTH);
+        assert_eq!(scanner.block_confirmations, DEFAULT_BLOCK_CONFIRMATIONS);
+    }
+
+    #[test]
+    fn builder_methods_update_configuration() {
+        let blocks_read_per_epoch = 42;
+        let reorg_rewind_depth = 12;
+        let block_confirmations = 7;
+
+        let scanner = BlockRangeScanner::new()
+            .with_blocks_read_per_epoch(blocks_read_per_epoch)
+            .with_reorg_rewind_depth(reorg_rewind_depth)
+            .with_block_confirmations(block_confirmations);
+
+        assert_eq!(scanner.blocks_read_per_epoch, blocks_read_per_epoch);
+        assert_eq!(scanner.block_confirmations, block_confirmations);
+    }
+
+    #[test]
+    fn service_status_reflects_internal_state() {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter);
+        let (mut service, _cmd) = Service::new(test_config(), provider);
+
+        let processed_count = 7;
+        let error_count = 2;
+        service.processed_count = processed_count;
+        service.error_count = error_count;
+        let hash = keccak256(b"random");
+        let block_number = 99;
+        service.current = Some(BlockHashAndNumber { hash, number: block_number });
+        service.websocket_connected = true;
+        service.subscriber = Some(mpsc::channel(1).0);
+
+        let status = service.get_status();
+
+        assert!(status.is_subscribed);
+        assert!(status.websocket_connected);
+        assert_eq!(status.processed_count, processed_count);
+        assert_eq!(status.error_count, error_count);
+        let last = status.last_synced_block.expect("last synced block is set");
+        assert_eq!(last.number, block_number);
+        assert_eq!(last.hash, hash);
+    }
+
+    #[tokio::test]
+    async fn send_to_subscriber_increments_processed_count() -> anyhow::Result<()> {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter);
+        let (mut service, _cmd) = Service::new(test_config(), provider);
+
+        let (tx, mut rx) = mpsc::channel(1);
+        service.subscriber = Some(tx);
+
+        let expected_range = 10..=11;
+        service.send_to_subscriber(Ok(expected_range.clone())).await;
+
+        assert_eq!(service.processed_count, 1);
+        assert!(service.subscriber.is_some());
+
+        let received = rx.recv().await.expect("range received")?;
+        assert_eq!(received, expected_range);
+
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn send_to_subscriber_removes_closed_channel() -> anyhow::Result<()> {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter);
+        let (mut service, _cmd) = Service::new(test_config(), provider);
+
+        let (tx, rx) = mpsc::channel(1);
+        service.websocket_connected = true;
+        service.subscriber = Some(tx);
+        // channel is closed
+        drop(rx);
+
+        service.send_to_subscriber(Ok(15..=15)).await;
+
+        assert!(service.subscriber.is_none());
+        assert!(!service.websocket_connected);
+        assert_eq!(service.processed_count, 0);
+
+        Ok(())
+    }
+
+    #[test]
+    fn handle_unsubscribe_clears_subscriber() {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter);
+        let (mut service, _cmd) = Service::new(test_config(), provider);
+
+        let (tx, _rx) = mpsc::channel(1);
+        service.websocket_connected = true;
+        service.subscriber = Some(tx);
+
+        service.handle_unsubscribe();
+
+        assert!(service.subscriber.is_none());
+        assert!(!service.websocket_connected);
+    }
+
     #[tokio::test]
     async fn live_mode_processes_all_blocks() -> anyhow::Result<()> {
         let anvil = Anvil::new().block_time_f64(0.01).try_spawn()?;
@@ -779,4 +913,81 @@ mod tests {
 
         Ok(())
     }
+
+    #[tokio::test]
+    async fn rewinds_on_detected_reorg() -> anyhow::Result<()> {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter.clone());
+
+        let mut config = test_config();
+        config.reorg_rewind_depth = 6;
+        let (mut service, _cmd) = Service::new(config.clone(), provider);
+
+        let original_height = 10;
+        let original_hash = keccak256(b"original block");
+        let original_block = mock_block(original_height, original_hash);
+        service.current =
+            Some(BlockHashAndNumber::from_header::<Ethereum>(original_block.header()));
+
+        let expected_rewind_height = original_height - config.reorg_rewind_depth;
+        let expected_rewind_hash = keccak256(b"rewound block");
+        let rewound_block = mock_block(expected_rewind_height, expected_rewind_hash);
+
+        // Mock provider responses for reorg detection and rewind:
+        // 1. get_block_by_hash(original_hash) -> None (block not found = reorg detected)
+        asserter.push_success(&Value::Null);
+        // 2. get_block_number() -> 12 (current chain head is at 12)
+        asserter.push_success(&json!(format!("0x{:x}", original_height + 2)));
+        // 3. get_block_by_number(expected_rewind_height) -> rewound_block
+        asserter.push_success(&rewound_block);
+
+        service.ensure_current_not_reorged().await?;
+
+        let current = service.current.expect("current block should be set after rewind");
+        assert_eq!(current.number, expected_rewind_height, "should rewind by reorg_rewind_depth");
+        assert_eq!(current.hash, expected_rewind_hash, "should use hash of block at rewind height");
+
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn buffered_messages_trim_ranges_prior_to_cutoff() -> anyhow::Result<()> {
+        let (buffer_tx, buffer_rx) = mpsc::channel(8);
+        buffer_tx.send(40..=44).await.unwrap();
+        buffer_tx.send(45..=54).await.unwrap();
+        buffer_tx.send(60..=61).await.unwrap();
+        drop(buffer_tx);
+
+        let (out_tx, mut out_rx) = mpsc::channel(8);
+
+        Service::<Ethereum>::process_buffered_messages(buffer_rx, out_tx, 50).await;
+
+        let mut forwarded = Vec::new();
+        while let Some(result) = out_rx.recv().await {
+            forwarded.push(result.unwrap());
+        }
+
+        assert_eq!(forwarded, vec![50..=54, 60..=61]);
+
+        Ok(())
+    }
+
+    #[tokio::test]
+    async fn forwards_errors_to_subscribers() -> anyhow::Result<()> {
+        let asserter = Asserter::new();
+        let provider = mocked_provider(asserter);
+        let (mut service, _cmd) = Service::new(test_config(), provider);
+
+        let (tx, mut rx) = mpsc::channel(1);
+        service.subscriber = Some(tx);
+
+        service.send_to_subscriber(Err(Error::WebSocketConnectionFailed(4))).await;
+
+        match rx.recv().await.expect("subscriber should stay open") {
+            Err(Error::WebSocketConnectionFailed(attempts)) => assert_eq!(attempts, 4),
+            other => panic!("unexpected message: {other:?}"),
+        }
+
+        Ok(())
+    }
 }