Merge pull request #942 from Cooldude2606/refactor/sub-filters-again

Make SubscriberFilter extend Set and expose errors in EventSubscriber

test/lib/subscriptions.test.js

@@ -792,7 +792,10 @@ describe("lib/subscriptions", function() {
 	});
 
 	describe("class EventSubscriber", function() {
-		let mockControl, eventSubscriber;
+		/** @type {MockControl} */
+		let mockControl;
+		/** @type {lib.EventSubscriber} */
+		let eventSubscriber;
 
 		beforeEach(function() {
 			mockControl = new MockControl(new MockConnector(
@@ -1120,6 +1123,25 @@ describe("lib/subscriptions", function() {
 				}
 				assert.equal(logged, undefined);
 			});
+
+			it("should expose errors through the snapshot", async function() {
+				eventSubscriber.control.sendTo = function() {
+					throw new lib.PermissionError("Permission denied");
+				};
+
+				const unsubscribe = eventSubscriber.subscribe(() => {});
+				await new Promise(r => setImmediate(r));
+				const [,, error1] = eventSubscriber.getSnapshot();
+				assert.ok(error1 instanceof lib.PermissionError);
+				assert.equal(error1.message, "Permission denied");
+				assert.equal(error1.code, "PermissionError");
+
+				eventSubscriber.control.sendTo = function() {};
+				unsubscribe();
+				await new Promise(r => setImmediate(r));
+				const [,, error2] = eventSubscriber.getSnapshot();
+				assert.deepEqual(error2, null);
+			});
 		});
 	});