exposing maxSubs as read-only property

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sub-events",
-  "version": "0.5.5",
+  "version": "0.6.0",
   "description": "Strongly-typed events in TypeScript, with monitored subscriptions.",
   "main": "dist/src/index.js",
   "types": "dist/src/index.d.ts",

src/event.ts

@@ -273,6 +273,17 @@ export class SubEvent<T = unknown> {
         return this._subs.length;
     }
 
+    /**
+     * Maximum number of subscribers that can receive events.
+     * Default is 0, meaning `no limit applies`.
+     *
+     * As the older subscriptions get cancelled, the newer ones
+     * outside of the maximum quota will start receiving events.
+     */
+    public get maxSubs(): number {
+        return this.options.maxSubs || 0;
+    }
+
     /**
      * Cancels all subscriptions.
      *
@@ -303,8 +314,7 @@ export class SubEvent<T = unknown> {
      * @hidden
      */
     protected _getRecipients(): ISubscriber<T>[] {
-        const max = this.options.maxSubs || 0;
-        const end = max > 0 ? max : this._subs.length;
+        const end = this.maxSubs > 0 ? this.maxSubs : this._subs.length;
         return this._subs.slice(0, end);
     }
 

test/event.spec.ts

@@ -5,6 +5,11 @@ const dummy = () => {
 };
 
 describe('SubEvent', () => {
+    it('must initialize correctly', () => {
+        const a = new SubEvent();
+        expect(a.count).to.eq(0);
+        expect(a.maxSubs).to.eq(0);
+    });
     it('must invoke subscription functions', () => {
         const a = new SubEvent<number>();
         const cb = () => 1;
@@ -70,6 +75,7 @@ describe('SubEvent', () => {
         const s2 = chai.spy(cb2);
         a.subscribe(s1);
         a.subscribe(s2);
+        expect(a.maxSubs).to.eq(1);
         expect(a.count).to.eq(2);
         a.emit(123, (count: number) => {
             expect(count).to.be.eq(1);