fix: fork reset (#857)

* fix fork reset

* try fix test

* fmt

crates/anvil/Cargo.toml

@@ -120,6 +120,7 @@ alloy-transport-ws.workspace = true
 alloy-json-rpc.workspace = true
 alloy-pubsub.workspace = true
 foundry-test-utils.workspace = true
+regex = { workspace = true, default-features = false }
 similar-asserts.workspace = true
 tokio = { workspace = true, features = ["full"] }
 

crates/anvil/src/eth/backend/mem/mod.rs

@@ -544,6 +544,26 @@ impl Backend {
                     *self.fork.write() = Some(fork);
                     *self.env.write() = env;
                 } else {
+                    // Set cache path on correct block
+                    {
+                        let maybe_fork_url = { self.node_config.read().await.eth_rpc_url.clone() };
+                        if let Some(fork_url) = maybe_fork_url {
+                            // Set the fork block number
+                            let mut node_config = self.node_config.write().await;
+                            node_config.fork_choice = Some(ForkChoice::Block(fork_block_number));
+
+                            let mut env = self.env.read().clone();
+                            let (forked_db, client_fork_config) = node_config
+                                .setup_fork_db_config(fork_url, &mut env, &self.fees)
+                                .await?;
+
+                            *self.db.write().await = Box::new(forked_db);
+                            let fork = ClientFork::new(client_fork_config, Arc::clone(&self.db));
+                            *self.fork.write() = Some(fork);
+                            *self.env.write() = env;
+                        }
+                    }
+
                     let gas_limit = self.node_config.read().await.fork_gas_limit(&fork_block);
                     let mut env = self.env.write();
 

crates/anvil/tests/it/fork.rs

@@ -1473,6 +1473,42 @@ async fn test_reset_dev_account_nonce() {
     assert!(receipt.status());
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn test_reset_updates_cache_path_when_rpc_url_not_provided() {
+    let config: NodeConfig = fork_config();
+
+    let (mut api, _handle) = spawn(config).await;
+    let info = api.anvil_node_info().await.unwrap();
+    let number = info.fork_config.fork_block_number.unwrap();
+    assert_eq!(number, BLOCK_NUMBER);
+
+    async fn get_block_from_cache_path(api: &mut EthApi) -> u64 {
+        let db = api.backend.get_db().read().await;
+        let cache_debug = format!("{:?}", db.maybe_inner().unwrap().cache());
+        let re = regex::Regex::new(r#"JsonBlockCacheDB \{ cache_path: Some\("([^"]+)"\)"#).unwrap();
+        let m = re
+            .captures_iter(&cache_debug)
+            .next()
+            .expect("must have JsonBlockCacheDB match")
+            .get(1)
+            .expect("must have matching path")
+            .as_str();
+        m.strip_suffix("/storage.json").unwrap().split("/").last().unwrap().parse::<u64>().unwrap()
+    }
+
+    assert_eq!(BLOCK_NUMBER, get_block_from_cache_path(&mut api).await);
+
+    // Reset to older block without specifying a new rpc url
+    api.anvil_reset(Some(Forking {
+        json_rpc_url: None,
+        block_number: Some(BLOCK_NUMBER - 1_000_000),
+    }))
+    .await
+    .unwrap();
+
+    assert_eq!(BLOCK_NUMBER - 1_000_000, get_block_from_cache_path(&mut api).await);
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn test_fork_get_account() {
     let (_api, handle) = spawn(fork_config()).await;

crates/zksync/core/src/vm/farcall.rs

@@ -173,7 +173,7 @@ impl FarCallHandler {
                 PrimitiveValue { value: return_fat_ptr.to_u256(), is_pointer: false };
 
             // Just rewriting `code_page` is very error-prone, since the same memory page would be
-            // re-used for decommitments. We'll use a different approach:
+            // reused for decommitments. We'll use a different approach:
             // - Set `previous_code_word` to the value that we want
             // - Set `previous_code_memory_page` to the current code page + `previous_super_pc` to 0
             //   (as it corresponds