pallet-message-queue: add queue pausing (#14318)

* pallet-message-queue: add queue pausing

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Fix build

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

* Remove check

Otherwise it would not start servicing queues that started paused
and became unpaused afterwards.

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>

substrate/frame/message-queue/src/mock.rs

@@ -84,6 +84,7 @@ impl Config for Test {
 	type MessageProcessor = RecordingMessageProcessor;
 	type Size = u32;
 	type QueueChangeHandler = RecordingQueueChangeHandler;
+	type QueuePausedQuery = MockedQueuePauser;
 	type HeapSize = HeapSize;
 	type MaxStale = MaxStale;
 	type ServiceWeight = ServiceWeight;
@@ -154,7 +155,8 @@ impl crate::weights::WeightInfo for MockedWeightInfo {
 
 parameter_types! {
 	pub static MessagesProcessed: Vec<(Vec<u8>, MessageOrigin)> = vec![];
-	pub static SuspendedQueues: Vec<MessageOrigin> = vec![];
+	/// Queues that should return `Yield` upon being processed.
+	pub static YieldingQueues: Vec<MessageOrigin> = vec![];
 }
 
 /// A message processor which records all processed messages into [`MessagesProcessed`].
@@ -205,7 +207,7 @@ impl ProcessMessage for RecordingMessageProcessor {
 /// Processed a mocked message. Messages that end with `badformat`, `corrupt`, `unsupported` or
 /// `yield` will fail with an error respectively.
 fn processing_message(msg: &[u8], origin: &MessageOrigin) -> Result<(), ProcessMessageError> {
-	if SuspendedQueues::get().contains(&origin) {
+	if YieldingQueues::get().contains(&origin) {
 		return Err(ProcessMessageError::Yield)
 	}
 
@@ -270,6 +272,17 @@ impl OnQueueChanged<MessageOrigin> for RecordingQueueChangeHandler {
 	}
 }
 
+parameter_types! {
+	pub static PausedQueues: Vec<MessageOrigin> = vec![];
+}
+
+pub struct MockedQueuePauser;
+impl QueuePausedQuery<MessageOrigin> for MockedQueuePauser {
+	fn is_paused(id: &MessageOrigin) -> bool {
+		PausedQueues::get().contains(id)
+	}
+}
+
 /// Create new test externalities.
 ///
 /// Is generic since it is used by the unit test, integration tests and benchmarks.
@@ -287,6 +300,12 @@ where
 	ext
 }
 
+/// Run this closure in test externalities.
+pub fn test_closure<R>(f: impl FnOnce() -> R) -> R {
+	let mut ext = new_test_ext::<Test>();
+	ext.execute_with(f)
+}
+
 /// Set the weight of a specific weight function.
 pub fn set_weight(name: &str, w: Weight) {
 	MockedWeightInfo::set_weight::<Test>(name, w);