contracts: Remove wat support from test fixtures (#3588)

In order to prepare for PolkaVM support I removed the wat support from
our test fixture crate.

- Removed redundant tests (invalid module checks are already inside the
prepare module where they belong
- Converted the gas_sync tests to Rust
- Moved the start function test to the `wasm` module

Cargo.lock

@@ -9634,7 +9634,6 @@ dependencies = [
  "tempfile",
  "toml 0.8.8",
  "twox-hash",
- "wat",
 ]
 
 [[package]]

substrate/frame/contracts/fixtures/Cargo.toml

@@ -11,7 +11,6 @@ description = "Fixtures for testing contracts pallet."
 workspace = true
 
 [dependencies]
-wat = "1"
 frame-system = { path = "../../system" }
 sp-runtime = { path = "../../../primitives/runtime" }
 anyhow = "1.0.0"

substrate/frame/contracts/fixtures/contracts/caller_is_origin_n.rs

@@ -14,12 +14,25 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-//! Valid module but missing the call function
+
+//! This fixture calls caller_is_origin `n` times.
+
 #![no_std]
 #![no_main]
 
-extern crate common;
+use common::input;
+use uapi::{HostFn, HostFnImpl as api};
 
 #[no_mangle]
 #[polkavm_derive::polkavm_export]
 pub extern "C" fn deploy() {}
+
+#[no_mangle]
+#[polkavm_derive::polkavm_export]
+pub extern "C" fn call() {
+	input!(n: u32, );
+
+	for _ in 0..n {
+		let _ = api::caller_is_origin();
+	}
+}

substrate/frame/contracts/fixtures/data/invalid_contract_no_memory.wat

@@ -1,5 +0,0 @@
-;; A valid contract which does nothing at all
-(module
-	(func (export "deploy"))
-	(func (export "call"))
-)

substrate/frame/contracts/fixtures/data/invalid_module.wat

@@ -1,8 +0,0 @@
-;; An invalid module
-(module
-	(func (export "deploy"))
-	(func (export "call")
-		;; imbalanced stack
-		(i32.const 7)
-	)
-)

substrate/frame/contracts/fixtures/data/run_out_of_gas_start_fn.wat

@@ -1,10 +0,0 @@
-(module
-	(import "env" "memory" (memory 1 1))
-	(start $start)
-	(func $start
-		(loop $inf (br $inf)) ;; just run out of gas
-		(unreachable)
-	)
-	(func (export "call"))
-	(func (export "deploy"))
-)

substrate/frame/contracts/fixtures/data/seal_input_noop.wat

@@ -1,14 +0,0 @@
-;; Everything prepared for the host function call, but no call is performed.
-(module
-	(import "seal0" "seal_input" (func $seal_input (param i32 i32)))
-	(import "env" "memory" (memory 1 1))
-
-	;; [0, 8) buffer to write input
-
-	;; [8, 12) size of the input buffer
-	(data (i32.const 8) "\04")
-
-	(func (export "call"))
-
-	(func (export "deploy"))
-)

substrate/frame/contracts/fixtures/data/seal_input_once.wat

@@ -1,22 +0,0 @@
-;; Stores a value of the passed size. The host function is called once.
-(module
-	(import "seal0" "seal_input" (func $seal_input (param i32 i32)))
-	(import "env" "memory" (memory 1 1))
-
-	;; [0, 8) buffer to write input
-
-	;; [8, 12) size of the input buffer
-	(data (i32.const 8) "\04")
-
-	(func (export "call")
-		;; instructions to consume engine fuel
-		(drop
-			(i32.const 42)
-		 )
-
- 	    (call $seal_input (i32.const 0) (i32.const 8))
-
-	 )
-
-	(func (export "deploy"))
-)

substrate/frame/contracts/fixtures/data/seal_input_twice.wat

@@ -1,28 +0,0 @@
-;; Stores a value of the passed size. The host function is called twice.
-(module
-	(import "seal0" "seal_input" (func $seal_input (param i32 i32)))
-	(import "env" "memory" (memory 1 1))
-
-	;; [0, 8) buffer to write input
-
-	;; [8, 12) size of the input buffer
-	(data (i32.const 8) "\04")
-
-	(func (export "call")
-		;; instructions to consume engine fuel
-		(drop
-			(i32.const 42)
-		 )
-
- 	    (call $seal_input (i32.const 0) (i32.const 8))
-
-		;; instructions to consume engine fuel
-		(drop
-			(i32.const 42)
-		 )
-
- 	    (call $seal_input (i32.const 0) (i32.const 8))
-	)
-
-	(func (export "deploy"))
-)

substrate/frame/contracts/fixtures/src/lib.rs

@@ -16,34 +16,7 @@
 // limitations under the License.
 
 use sp_runtime::traits::Hash;
-use std::{env::var, fs, path::PathBuf};
-
-fn wat_root_dir() -> PathBuf {
-	match (var("CARGO_MANIFEST_DIR"), var("CARGO_PKG_NAME")) {
-		// When `CARGO_MANIFEST_DIR` is not set, Rust resolves relative paths from the root folder
-		(Err(_), _) => "substrate/frame/contracts/fixtures/data".into(),
-		(Ok(path), Ok(s)) if s == "pallet-contracts" => PathBuf::from(path).join("fixtures/data"),
-		(Ok(path), Ok(s)) if s == "pallet-contracts-mock-network" =>
-			PathBuf::from(path).parent().unwrap().join("fixtures/data"),
-		(Ok(_), pkg_name) => panic!("Failed to resolve fixture dir for tests from {pkg_name:?}."),
-	}
-}
-
-/// Load a given wasm module represented by a .wat file and returns a wasm binary contents along
-/// with it's hash.
-///
-/// The fixture files are located under the `fixtures/` directory.
-fn legacy_compile_module<T>(
-	fixture_name: &str,
-) -> anyhow::Result<(Vec<u8>, <T::Hashing as Hash>::Output)>
-where
-	T: frame_system::Config,
-{
-	let fixture_path = wat_root_dir().join(format!("{fixture_name}.wat"));
-	let wasm_binary = wat::parse_file(fixture_path)?;
-	let code_hash = T::Hashing::hash(&wasm_binary);
-	Ok((wasm_binary, code_hash))
-}
+use std::{fs, path::PathBuf};
 
 /// Load a given wasm module and returns a wasm binary contents along with it's hash.
 /// Use the legacy compile_module as fallback, if the rust fixture does not exist yet.
@@ -53,15 +26,11 @@ pub fn compile_module<T>(
 where
 	T: frame_system::Config,
 {
-	let out_dir: std::path::PathBuf = env!("OUT_DIR").into();
+	let out_dir: PathBuf = env!("OUT_DIR").into();
 	let fixture_path = out_dir.join(format!("{fixture_name}.wasm"));
-	match fs::read(fixture_path) {
-		Ok(wasm_binary) => {
-			let code_hash = T::Hashing::hash(&wasm_binary);
-			Ok((wasm_binary, code_hash))
-		},
-		Err(_) => legacy_compile_module::<T>(fixture_name),
-	}
+	let binary = fs::read(fixture_path)?;
+	let code_hash = T::Hashing::hash(&binary);
+	Ok((binary, code_hash))
 }
 
 #[cfg(test)]

substrate/frame/contracts/src/tests.rs

@@ -852,27 +852,6 @@ fn deposit_event_max_value_limit() {
 	});
 }
 
-// Fail out of fuel (ref_time weight) inside the start function.
-#[test]
-fn run_out_of_fuel_start_fun() {
-	let (wasm, _code_hash) = compile_module::<Test>("run_out_of_gas_start_fn").unwrap();
-	ExtBuilder::default().existential_deposit(50).build().execute_with(|| {
-		let _ = <Test as Config>::Currency::set_balance(&ALICE, 1_000_000);
-		assert_err_ignore_postinfo!(
-			Contracts::instantiate_with_code(
-				RuntimeOrigin::signed(ALICE),
-				0,
-				Weight::from_parts(1_000_000_000_000, u64::MAX),
-				None,
-				wasm,
-				vec![],
-				vec![],
-			),
-			Error::<Test>::OutOfGas,
-		);
-	});
-}
-
 // Fail out of fuel (ref_time weight) in the engine.
 #[test]
 fn run_out_of_fuel_engine() {
@@ -956,50 +935,15 @@ fn run_out_of_fuel_host() {
 
 #[test]
 fn gas_syncs_work() {
-	let (wasm0, _code_hash) = compile_module::<Test>("seal_input_noop").unwrap();
-	let (wasm1, _code_hash) = compile_module::<Test>("seal_input_once").unwrap();
-	let (wasm2, _code_hash) = compile_module::<Test>("seal_input_twice").unwrap();
+	let (code, _code_hash) = compile_module::<Test>("caller_is_origin_n").unwrap();
 	ExtBuilder::default().existential_deposit(200).build().execute_with(|| {
 		let _ = <Test as Config>::Currency::set_balance(&ALICE, 1_000_000);
-		// Instantiate noop contract.
-		let addr0 = Contracts::bare_instantiate(
+		let addr = Contracts::bare_instantiate(
 			ALICE,
 			0,
 			GAS_LIMIT,
 			None,
-			Code::Upload(wasm0),
-			vec![],
-			vec![],
-			DebugInfo::Skip,
-			CollectEvents::Skip,
-		)
-		.result
-		.unwrap()
-		.account_id;
-
-		// Instantiate 1st contract.
-		let addr1 = Contracts::bare_instantiate(
-			ALICE,
-			0,
-			GAS_LIMIT,
-			None,
-			Code::Upload(wasm1),
-			vec![],
-			vec![],
-			DebugInfo::Skip,
-			CollectEvents::Skip,
-		)
-		.result
-		.unwrap()
-		.account_id;
-
-		// Instantiate 2nd contract.
-		let addr2 = Contracts::bare_instantiate(
-			ALICE,
-			0,
-			GAS_LIMIT,
-			None,
-			Code::Upload(wasm2),
+			Code::Upload(code),
 			vec![],
 			vec![],
 			DebugInfo::Skip,
@@ -1011,11 +955,11 @@ fn gas_syncs_work() {
 
 		let result = Contracts::bare_call(
 			ALICE,
-			addr0,
+			addr.clone(),
 			0,
 			GAS_LIMIT,
 			None,
-			1u8.to_le_bytes().to_vec(),
+			0u32.encode(),
 			DebugInfo::Skip,
 			CollectEvents::Skip,
 			Determinism::Enforced,
@@ -1025,27 +969,28 @@ fn gas_syncs_work() {
 
 		let result = Contracts::bare_call(
 			ALICE,
-			addr1,
+			addr.clone(),
 			0,
 			GAS_LIMIT,
 			None,
-			1u8.to_le_bytes().to_vec(),
+			1u32.encode(),
 			DebugInfo::Skip,
 			CollectEvents::Skip,
 			Determinism::Enforced,
 		);
 		assert_ok!(result.result);
 		let gas_consumed_once = result.gas_consumed.ref_time();
-		let host_consumed_once = <Test as Config>::Schedule::get().host_fn_weights.input.ref_time();
+		let host_consumed_once =
+			<Test as Config>::Schedule::get().host_fn_weights.caller_is_origin.ref_time();
 		let engine_consumed_once = gas_consumed_once - host_consumed_once - engine_consumed_noop;
 
 		let result = Contracts::bare_call(
 			ALICE,
-			addr2,
+			addr,
 			0,
 			GAS_LIMIT,
 			None,
-			1u8.to_le_bytes().to_vec(),
+			2u32.encode(),
 			DebugInfo::Skip,
 			CollectEvents::Skip,
 			Determinism::Enforced,
@@ -4453,96 +4398,6 @@ fn contract_reverted() {
 	});
 }
 
-#[test]
-fn code_rejected_error_works() {
-	ExtBuilder::default().existential_deposit(200).build().execute_with(|| {
-		let _ = <Test as Config>::Currency::set_balance(&ALICE, 1_000_000);
-
-		let (wasm, _) = compile_module::<Test>("invalid_module").unwrap();
-		assert_noop!(
-			Contracts::upload_code(
-				RuntimeOrigin::signed(ALICE),
-				wasm.clone(),
-				None,
-				Determinism::Enforced
-			),
-			<Error<Test>>::CodeRejected,
-		);
-		let result = Contracts::bare_instantiate(
-			ALICE,
-			0,
-			GAS_LIMIT,
-			None,
-			Code::Upload(wasm),
-			vec![],
-			vec![],
-			DebugInfo::UnsafeDebug,
-			CollectEvents::Skip,
-		);
-		assert_err!(result.result, <Error<Test>>::CodeRejected);
-		assert_eq!(
-			std::str::from_utf8(&result.debug_message).unwrap(),
-			"Can't load the module into wasmi!"
-		);
-
-		let (wasm, _) = compile_module::<Test>("invalid_contract_no_call").unwrap();
-		assert_noop!(
-			Contracts::upload_code(
-				RuntimeOrigin::signed(ALICE),
-				wasm.clone(),
-				None,
-				Determinism::Enforced
-			),
-			<Error<Test>>::CodeRejected,
-		);
-
-		let result = Contracts::bare_instantiate(
-			ALICE,
-			0,
-			GAS_LIMIT,
-			None,
-			Code::Upload(wasm),
-			vec![],
-			vec![],
-			DebugInfo::UnsafeDebug,
-			CollectEvents::Skip,
-		);
-		assert_err!(result.result, <Error<Test>>::CodeRejected);
-		assert_eq!(
-			std::str::from_utf8(&result.debug_message).unwrap(),
-			"call function isn't exported"
-		);
-
-		let (wasm, _) = compile_module::<Test>("invalid_contract_no_memory").unwrap();
-		assert_noop!(
-			Contracts::upload_code(
-				RuntimeOrigin::signed(ALICE),
-				wasm.clone(),
-				None,
-				Determinism::Enforced
-			),
-			<Error<Test>>::CodeRejected,
-		);
-
-		let result = Contracts::bare_instantiate(
-			ALICE,
-			0,
-			GAS_LIMIT,
-			None,
-			Code::Upload(wasm),
-			vec![],
-			vec![],
-			DebugInfo::UnsafeDebug,
-			CollectEvents::Skip,
-		);
-		assert_err!(result.result, <Error<Test>>::CodeRejected);
-		assert_eq!(
-			std::str::from_utf8(&result.debug_message).unwrap(),
-			"No memory import found in the module"
-		);
-	});
-}
-
 #[test]
 fn set_code_hash() {
 	let (wasm, code_hash) = compile_module::<Test>("set_code_hash").unwrap();

substrate/frame/contracts/src/wasm/mod.rs

@@ -3442,4 +3442,22 @@ mod tests {
 			runtime.read_sandbox_memory_as(&memory, 0u32).unwrap();
 		assert_eq!(decoded.into_inner(), data);
 	}
+
+	#[test]
+	fn run_out_of_gas_in_start_fn() {
+		const CODE: &str = r#"
+(module
+	(import "env" "memory" (memory 1 1))
+	(start $start)
+	(func $start
+		(loop $inf (br $inf)) ;; just run out of gas
+		(unreachable)
+	)
+	(func (export "call"))
+	(func (export "deploy"))
+)
+"#;
+		let mut mock_ext = MockExt::default();
+		assert_err!(execute(&CODE, vec![], &mut mock_ext), <Error<Test>>::OutOfGas);
+	}
 }