core-fellowship: allow infinite demotion period (paritytech#2828)

substrate/frame/core-fellowship/src/benchmarking.rs

@@ -53,6 +53,19 @@ mod benchmarks {
 		Ok(member)
 	}
 
+	fn set_benchmark_params<T: Config<I>, I: 'static>() -> Result<(), BenchmarkError> {
+		let params = ParamsType {
+			active_salary: [100u32.into(); 9],
+			passive_salary: [10u32.into(); 9],
+			demotion_period: [100u32.into(); 9],
+			min_promotion_period: [100u32.into(); 9],
+			offboard_timeout: 1u32.into(),
+		};
+
+		CoreFellowship::<T, I>::set_params(RawOrigin::Root.into(), Box::new(params))?;
+		Ok(())
+	}
+
 	#[benchmark]
 	fn set_params() -> Result<(), BenchmarkError> {
 		let params = ParamsType {
@@ -72,6 +85,8 @@ mod benchmarks {
 
 	#[benchmark]
 	fn bump_offboard() -> Result<(), BenchmarkError> {
+		set_benchmark_params::<T, I>()?;
+
 		let member = make_member::<T, I>(0)?;
 
 		// Set it to the max value to ensure that any possible auto-demotion period has passed.
@@ -89,6 +104,8 @@ mod benchmarks {
 
 	#[benchmark]
 	fn bump_demote() -> Result<(), BenchmarkError> {
+		set_benchmark_params::<T, I>()?;
+
 		let member = make_member::<T, I>(2)?;
 
 		// Set it to the max value to ensure that any possible auto-demotion period has passed.

substrate/frame/core-fellowship/src/lib.rs

@@ -298,6 +298,11 @@ pub mod pallet {
 				let rank_index = Self::rank_to_index(rank).ok_or(Error::<T, I>::InvalidRank)?;
 				params.demotion_period[rank_index]
 			};
+
+			if demotion_period.is_zero() {
+				return Err(Error::<T, I>::NothingDoing.into())
+			}
+
 			let demotion_block = member.last_proof.saturating_add(demotion_period);
 
 			// Ensure enough time has passed.

substrate/frame/core-fellowship/src/tests.rs

@@ -306,6 +306,28 @@ fn offboard_works() {
 	});
 }
 
+#[test]
+fn infinite_demotion_period_works() {
+	new_test_ext().execute_with(|| {
+		let params = ParamsType {
+			active_salary: [10; 9],
+			passive_salary: [10; 9],
+			min_promotion_period: [10; 9],
+			demotion_period: [0; 9],
+			offboard_timeout: 0,
+		};
+		assert_ok!(CoreFellowship::set_params(signed(1), Box::new(params)));
+
+		set_rank(0, 0);
+		assert_ok!(CoreFellowship::import(signed(0)));
+		set_rank(1, 1);
+		assert_ok!(CoreFellowship::import(signed(1)));
+
+		assert_noop!(CoreFellowship::bump(signed(0), 0), Error::<Test>::NothingDoing);
+		assert_noop!(CoreFellowship::bump(signed(0), 1), Error::<Test>::NothingDoing);
+	});
+}
+
 #[test]
 fn proof_postpones_auto_demote() {
 	new_test_ext().execute_with(|| {