Feature gate do_task in frame_system (#2707)

https://github.com/paritytech/polkadot-sdk/pull/1343/ introduced Tasks
API. This one moves `do_task` call in frame_system under the
experimental flag, till the previous one is audited.

---------

Co-authored-by: command-bot <>

substrate/bin/node/runtime/Cargo.toml

@@ -407,3 +407,8 @@ try-runtime = [
 	"pallet-whitelist/try-runtime",
 	"sp-runtime/try-runtime",
 ]
+experimental = [
+	"frame-support/experimental",
+	"frame-system/experimental",
+	"pallet-example-tasks/experimental",
+]

substrate/frame/examples/tasks/Cargo.toml

@@ -53,3 +53,4 @@ try-runtime = [
 	"frame-system/try-runtime",
 	"sp-runtime/try-runtime",
 ]
+experimental = ["frame-support/experimental", "frame-system/experimental"]

substrate/frame/examples/tasks/src/tests.rs

@@ -18,10 +18,13 @@
 //! Tests for `pallet-example-tasks`.
 #![cfg(test)]
 
-use crate::{mock::*, Numbers, Total};
-use frame_support::{assert_noop, assert_ok, traits::Task};
+use crate::{mock::*, Numbers};
+use frame_support::traits::Task;
 use sp_runtime::BuildStorage;
 
+#[cfg(feature = "experimental")]
+use frame_support::{assert_noop, assert_ok};
+
 // This function basically just builds a genesis storage key/value store according to
 // our desired mockup.
 pub fn new_test_ext() -> sp_io::TestExternalities {
@@ -89,6 +92,7 @@ fn task_index_works_at_runtime_level() {
 	});
 }
 
+#[cfg(feature = "experimental")]
 #[test]
 fn task_execution_works() {
 	new_test_ext().execute_with(|| {
@@ -105,11 +109,12 @@ fn task_execution_works() {
 		assert_ok!(System::do_task(RuntimeOrigin::signed(1), task.clone(),));
 		assert_eq!(Numbers::<Runtime>::get(0), Some(1));
 		assert_eq!(Numbers::<Runtime>::get(1), None);
-		assert_eq!(Total::<Runtime>::get(), (1, 4));
+		assert_eq!(crate::Total::<Runtime>::get(), (1, 4));
 		System::assert_last_event(frame_system::Event::<Runtime>::TaskCompleted { task }.into());
 	});
 }
 
+#[cfg(feature = "experimental")]
 #[test]
 fn task_execution_fails_for_invalid_task() {
 	new_test_ext().execute_with(|| {

substrate/frame/support/test/Cargo.toml

@@ -61,7 +61,10 @@ std = [
 	"sp-version/std",
 	"test-pallet/std",
 ]
-experimental = ["frame-support/experimental"]
+experimental = [
+	"frame-support/experimental",
+	"frame-system/experimental",
+]
 try-runtime = [
 	"frame-executive/try-runtime",
 	"frame-support/try-runtime",

substrate/frame/support/test/tests/pallet_outer_enums_explicit.rs

@@ -90,7 +90,9 @@ fn module_error_outer_enum_expand_explicit() {
 			frame_system::Error::NonDefaultComposite => (),
 			frame_system::Error::NonZeroRefCount => (),
 			frame_system::Error::CallFiltered => (),
+			#[cfg(feature = "experimental")]
 			frame_system::Error::InvalidTask => (),
+			#[cfg(feature = "experimental")]
 			frame_system::Error::FailedTask => (),
 			frame_system::Error::__Ignore(_, _) => (),
 		},

substrate/frame/support/test/tests/pallet_outer_enums_implicit.rs

@@ -90,7 +90,9 @@ fn module_error_outer_enum_expand_implicit() {
 			frame_system::Error::NonDefaultComposite => (),
 			frame_system::Error::NonZeroRefCount => (),
 			frame_system::Error::CallFiltered => (),
+			#[cfg(feature = "experimental")]
 			frame_system::Error::InvalidTask => (),
+			#[cfg(feature = "experimental")]
 			frame_system::Error::FailedTask => (),
 			frame_system::Error::__Ignore(_, _) => (),
 		},

substrate/frame/system/Cargo.toml

@@ -56,6 +56,7 @@ runtime-benchmarks = [
 	"sp-runtime/runtime-benchmarks",
 ]
 try-runtime = ["frame-support/try-runtime", "sp-runtime/try-runtime"]
+experimental = ["frame-support/experimental"]
 
 [[bench]]
 name = "bench"

substrate/frame/system/src/lib.rs

@@ -323,9 +323,11 @@ pub mod pallet {
 			#[inject_runtime_type]
 			type RuntimeCall = ();
 
-			/// Converts a module to the index of the module, injected by `construct_runtime!`.
+			/// The aggregated Task type, injected by `construct_runtime!`.
 			#[inject_runtime_type]
 			type RuntimeTask = ();
+
+			/// Converts a module to the index of the module, injected by `construct_runtime!`.
 			#[inject_runtime_type]
 			type PalletInfo = ();
 
@@ -637,6 +639,7 @@ pub mod pallet {
 			Ok(().into())
 		}
 
+		#[cfg(feature = "experimental")]
 		#[pallet::call_index(8)]
 		#[pallet::weight(task.weight())]
 		pub fn do_task(origin: OriginFor<T>, task: T::RuntimeTask) -> DispatchResultWithPostInfo {
@@ -675,10 +678,13 @@ pub mod pallet {
 		KilledAccount { account: T::AccountId },
 		/// On on-chain remark happened.
 		Remarked { sender: T::AccountId, hash: T::Hash },
+		#[cfg(feature = "experimental")]
 		/// A [`Task`] has started executing
 		TaskStarted { task: T::RuntimeTask },
+		#[cfg(feature = "experimental")]
 		/// A [`Task`] has finished executing.
 		TaskCompleted { task: T::RuntimeTask },
+		#[cfg(feature = "experimental")]
 		/// A [`Task`] failed during execution.
 		TaskFailed { task: T::RuntimeTask, err: DispatchError },
 	}
@@ -702,8 +708,10 @@ pub mod pallet {
 		NonZeroRefCount,
 		/// The origin filter prevent the call to be dispatched.
 		CallFiltered,
+		#[cfg(feature = "experimental")]
 		/// The specified [`Task`] is not valid.
 		InvalidTask,
+		#[cfg(feature = "experimental")]
 		/// The specified [`Task`] failed during execution.
 		FailedTask,
 	}