Fix RPC error on starknet_getBlockTransactionCount

crates/starknet-devnet-server/src/api/json_rpc/endpoints.rs

@@ -271,7 +271,7 @@ impl JsonRpcHandler {
         let num_trans_count = self.api.starknet.read().await.get_block_txs_count(block_id.as_ref());
         match num_trans_count {
             Ok(count) => Ok(StarknetResponse::BlockTransactionCount(count).into()),
-            Err(_) => Err(ApiError::NoBlocks),
+            Err(_) => Err(ApiError::BlockNotFound),
         }
     }
 

crates/starknet-devnet/tests/test_get_block_txs_count.rs

@@ -0,0 +1,35 @@
+pub mod common;
+
+mod get_block_txs_count_tests {
+
+    use starknet_rs_core::types::{BlockId, BlockTag, StarknetError};
+    use starknet_rs_providers::{Provider, ProviderError};
+
+    use crate::common::background_devnet::BackgroundDevnet;
+
+    #[tokio::test]
+    async fn test_invalid_block() {
+        let devnet = BackgroundDevnet::spawn().await.expect("Could not start Devnet");
+
+        let res = devnet
+            .json_rpc_client
+            .get_block_transaction_count(BlockId::Number(9000000000))
+            .await
+            .unwrap_err();
+        match res {
+            ProviderError::StarknetError(StarknetError::BlockNotFound) => (),
+            _ => panic!("Invalid error: {res:?}"),
+        }
+    }
+
+    #[tokio::test]
+    async fn test_valid_block() {
+        let devnet = BackgroundDevnet::spawn().await.expect("Could not start Devnet");
+
+        devnet
+            .json_rpc_client
+            .get_block_transaction_count(BlockId::Tag(BlockTag::Latest))
+            .await
+            .unwrap();
+    }
+}