feat: chain id in runner

crates/katana/runner/macro/src/config.rs

@@ -18,6 +18,7 @@ pub struct Configuration {
     pub db_dir: Option<syn::Expr>,
     pub block_time: Option<syn::Expr>,
     pub log_path: Option<syn::Expr>,
+    pub chain_id: Option<syn::Expr>,
 }
 
 impl Configuration {
@@ -32,6 +33,7 @@ impl Configuration {
             validation: None,
             block_time: None,
             crate_name: None,
+            chain_id: None,
         }
     }
 
@@ -105,6 +107,19 @@ impl Configuration {
         self.accounts = Some(accounts);
         Ok(())
     }
+
+    fn set_chain_id(
+        &mut self,
+        chain_id: syn::Expr,
+        span: proc_macro2::Span,
+    ) -> Result<(), syn::Error> {
+        if self.chain_id.is_some() {
+            return Err(syn::Error::new(span, "`chain_id` set multiple times."));
+        }
+
+        self.chain_id = Some(chain_id);
+        Ok(())
+    }
 }
 
 enum RunnerArg {
@@ -113,6 +128,7 @@ enum RunnerArg {
     Validation,
     Accounts,
     DbDir,
+    ChainId,
 }
 
 impl std::str::FromStr for RunnerArg {
@@ -125,9 +141,10 @@ impl std::str::FromStr for RunnerArg {
             "validation" => Ok(RunnerArg::Validation),
             "accounts" => Ok(RunnerArg::Accounts),
             "db_dir" => Ok(RunnerArg::DbDir),
+            "chain_id" => Ok(RunnerArg::ChainId),
             _ => Err(format!(
                 "Unknown attribute {s} is specified; expected one of: `fee`, `validation`, \
-                 `accounts`, `db_dir`, `block_time`",
+                 `accounts`, `db_dir`, `block_time`, `chain_id`",
             )),
         }
     }
@@ -172,7 +189,9 @@ pub fn build_config(
                     RunnerArg::DbDir => {
                         config.set_db_dir(expr.clone(), Spanned::span(&namevalue))?
                     }
-
+                    RunnerArg::ChainId => {
+                        config.set_chain_id(expr.clone(), Spanned::span(&namevalue))?
+                    }
                     RunnerArg::Fee => config.set_fee(expr.clone(), Spanned::span(&namevalue))?,
                 }
             }

crates/katana/runner/macro/src/entry.rs

@@ -74,7 +74,11 @@ pub fn parse_knobs(input: ItemFn, is_test: bool, config: Configuration) -> Token
     }
 
     if let Some(value) = config.log_path {
-        cfg = quote_spanned! (last_stmt_start_span=> #cfg, log_path: Some(#value), );
+        cfg = quote_spanned! (last_stmt_start_span=> #cfg log_path: Some(#value), );
+    }
+
+    if let Some(value) = config.chain_id {
+        cfg = quote_spanned! (last_stmt_start_span=> #cfg chain_id: Some(#value), );
     }
 
     if config.dev {

crates/katana/runner/src/lib.rs

@@ -67,6 +67,8 @@ pub struct KatanaRunnerConfig {
     pub db_dir: Option<PathBuf>,
     /// Whether to run the katana runner with the `dev` rpc endpoints.
     pub dev: bool,
+    /// The chain id to use.
+    pub chain_id: Option<Felt>,
 }
 
 impl Default for KatanaRunnerConfig {
@@ -82,6 +84,7 @@ impl Default for KatanaRunnerConfig {
             messaging: None,
             db_dir: None,
             dev: false,
+            chain_id: None,
         }
     }
 }
@@ -123,6 +126,10 @@ impl KatanaRunner {
             .dev(config.dev)
             .fee(!config.disable_fee);
 
+        if let Some(id) = config.chain_id {
+            builder = builder.chain_id(id);
+        }
+
         if let Some(block_time_ms) = config.block_time {
             builder = builder.block_time(block_time_ms);
         }

crates/katana/runner/tests/runner.rs

@@ -1,11 +1,20 @@
 use katana_runner::RunnerCtx;
+use starknet::macros::short_string;
 use starknet::providers::Provider;
 
 #[katana_runner::test(fee = false, accounts = 7)]
 fn simple(runner: &RunnerCtx) {
     assert_eq!(runner.accounts().len(), 7);
 }
 
+#[tokio::test(flavor = "multi_thread")]
+#[katana_runner::test(chain_id = short_string!("SN_SEPOLIA"))]
+async fn custom_chain_id(runner: &RunnerCtx) {
+    let provider = runner.provider();
+    let id = provider.chain_id().await.unwrap();
+    assert_eq!(id, short_string!("SN_SEPOLIA"));
+}
+
 #[katana_runner::test]
 fn with_return(_: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
     Ok(())
@@ -15,6 +24,7 @@ fn with_return(_: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
 #[katana_runner::test]
 async fn with_async(ctx: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
     let provider = ctx.provider();
-    let _ = provider.chain_id().await?;
+    let id = provider.chain_id().await?;
+    assert_eq!(id, short_string!("KATANA"));
     Ok(())
 }