fix(core-event-emitter): ensure the event listener won’t exceed the max listener count

__tests__/unit/core-event-emitter/emitter.test.ts

@@ -1,5 +1,5 @@
-import EventEmitter from "eventemitter3";
 import { plugin } from "../../../packages/core-event-emitter/src";
+import { EventEmitter } from "../../../packages/core-event-emitter/src/emitter";
 
 const emitter = plugin.register();
 

packages/core-event-emitter/package.json

@@ -17,9 +17,6 @@
         "build:watch": "yarn clean && yarn compile -w",
         "clean": "del dist"
     },
-    "dependencies": {
-        "eventemitter3": "^3.1.0"
-    },
     "publishConfig": {
         "access": "public"
     },

packages/core-event-emitter/src/emitter.ts

@@ -0,0 +1,30 @@
+import { EventEmitter as NativeEmitter } from "events";
+
+export class EventEmitter {
+    private readonly emitter: NativeEmitter = new NativeEmitter();
+
+    public emit(event: string | symbol, args: any): boolean {
+        return this.emitter.emit(event, args);
+    }
+
+    public on(event: string | symbol, listener: (...args: any) => void): void {
+        this.ensureMaxListenerCount(event);
+
+        this.emitter.on(event, listener);
+    }
+
+    public once(event: string | symbol, listener: (...args: any) => void): void {
+        this.ensureMaxListenerCount(event);
+
+        this.emitter.once(event, listener);
+    }
+
+    private ensureMaxListenerCount(event): void {
+        const maxListeners = this.emitter.getMaxListeners();
+        const listenerCount = this.emitter.listenerCount(event);
+
+        if (listenerCount >= maxListeners) {
+            this.emitter.setMaxListeners(maxListeners + 1);
+        }
+    }
+}

packages/core-event-emitter/src/index.ts

@@ -1,4 +1,4 @@
-import EventEmitter from "eventemitter3";
+import { EventEmitter } from "./emitter";
 
 export const plugin = {
     pkg: require("../package.json"),

packages/core-interfaces/package.json

@@ -24,8 +24,7 @@
     },
     "dependencies": {
         "@arkecosystem/crypto": "^2.3.0-next.2",
-        "awilix": "^4.2.1",
-        "eventemitter3": "^3.1.0"
+        "awilix": "^4.2.1"
     },
     "publishConfig": {
         "access": "public"

packages/core-interfaces/src/core-event-emitter/index.ts

@@ -1,2 +1,3 @@
-import EventEmitter from "eventemitter3";
+import { EventEmitter } from "events";
+
 export { EventEmitter };

yarn.lock

@@ -5577,11 +5577,6 @@ event-lite@^0.1.1:
   resolved "https://registry.yarnpkg.com/event-lite/-/event-lite-0.1.2.tgz#838a3e0fdddef8cc90f128006c8e55a4e4e4c11b"
   integrity sha512-HnSYx1BsJ87/p6swwzv+2v6B4X+uxUteoDfRxsAb1S1BePzQqOLevVmkdA15GHJVd9A9Ok6wygUR18Hu0YeV9g==
 
-eventemitter3@^3.1.0:
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/eventemitter3/-/eventemitter3-3.1.0.tgz#090b4d6cdbd645ed10bf750d4b5407942d7ba163"
-  integrity sha512-ivIvhpq/Y0uSjcHDcOIccjmYjGLcP09MFGE7ysAwkAvkXfpZlC985pH2/ui64DKazbTW/4kN3yqozUxlXzI6cA==
-
 events@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/events/-/events-3.0.0.tgz#9a0a0dfaf62893d92b875b8f2698ca4114973e88"