strict-event-emitter - npm Package Compare versions

Comparing version 0.3.1 to 0.3.2

lib/index.d.ts

@@ -0,2 +1,4 @@
+export * from './Emitter';
+export * from './MemoryLeakError';
 export * from './StrictEventEmitter';
 export * from './StrictEventTarget';

lib/index.js

 "use strict";
 var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
     if (k2 === undefined) k2 = k;
-    Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } });
+    var desc = Object.getOwnPropertyDescriptor(m, k);
+    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
+      desc = { enumerable: true, get: function() { return m[k]; } };
+    }
+    Object.defineProperty(o, k2, desc);
 }) : (function(o, m, k, k2) {
@@ -13,3 +17,5 @@ if (k2 === undefined) k2 = k;
 Object.defineProperty(exports, "__esModule", { value: true });
+__exportStar(require("./Emitter"), exports);
+__exportStar(require("./MemoryLeakError"), exports);
 __exportStar(require("./StrictEventEmitter"), exports);
 __exportStar(require("./StrictEventTarget"), exports);

lib/StrictEventEmitter.d.ts

@@ -0,1 +1,2 @@
+/// <reference types="node" />
 import { EventEmitter } from 'events';
@@ -2,0 +3,0 @@ export declare type EventMapType = Record<string | symbol | number, any>;

lib/StrictEventTarget.js

@@ -25,2 +25,3 @@ "use strict";
 class StrictMessageEvent extends MessageEvent {
+    type;
     constructor(type, eventInitDict) {
@@ -27,0 +28,0 @@ super(type, eventInitDict);

package.json

 {
   "name": "strict-event-emitter",
-  "version": "0.3.1",
-  "description": "Type-safe \"EventEmitter\" for everyday use",
+  "version": "0.3.2",
+  "description": "Type-safe implementation of EventEmitter for browser and Node.js",
   "main": "lib/index.js",
-  "typings": "lib/index.js",
+  "typings": "lib/index.d.ts",
   "repository": "[e-mail]:open-draft/strict-event-emitter.git",
@@ -19,3 +19,2 @@ "author": "Artem Zakharchenko <[e-mail]>",
   "files": [
-    "README.md",
     "lib"
@@ -26,8 +25,9 @@ ],
     "@types/events": "^3.0.0",
-    "@types/jest": "^26.0.19",
-    "jest": "^26.6.3",
+    "@types/jest": "^29.2.4",
+    "jest": "^29.3.1",
+    "jest-extended": "^3.2.0",
     "rimraf": "^3.0.2",
-    "ts-jest": "^26.4.4",
+    "ts-jest": "^29.0.3",
     "ts-node": "^9.1.1",
-    "typescript": "^4.1.3"
+    "typescript": "4.8"
   },
@@ -34,0 +34,0 @@ "dependencies": {

README.md

 # Strict Event Emitter
 
-`EventEmitter` mirror that restricts emitting/handling events other than specified in an interface.
+A type-safe implementation of `EventEmitter` for browser and Node.js.
 
-## Features
-
-- Restricts emitting of the unknown event types.
-- Infers emitted data types from the listener's call signature.
-
 ## Motivation
 
-The native `EventEmitter` class uses a generic `string` to describe what type of events can be emitted. In most cases you design a strict set of events that you expect your emitter to emit/listen to. This package helps you to type-annotate an emitter instance to produce type violations if an unknown event is emitted/listened to.
+Despite event emitters potentially accepting any runtime value, defining a strict event contract is crucial when developing complex event-driven architectures. Unfortunately, the native type definitions for Node's `EventEmitter` annotate event names as `string`, which forbids any stricter type validation.
 
 ```js
+// index.js
 const emitter = new EventEmitter()
 
-emitter.addListener('ping', (n: number) => {})
+// Let's say our application expects a "ping"
+// event with the number payload.
+emitter.on('ping', (n: number) => {})
 
-// The "pong" event is not expected, but will be emitted anyway.
-// The data passed to the event is incompatible with the expected type.
-emitter.emit('pong', 'not a number')
+// We can, however, emit a different event by mistake.
+emitter.emit('poing', 1)
+
+// Or even the correct event with the wrong data.
+emitter.emit('ping', 'wait, not a number')
 ```
 
+The purpose of this library is to provide an `EventEmitter` instance that can accept a generic describing the expected events contract.
+
 ```ts
-import { StrictEventEmitter } from 'strict-event-emitter'
+import { Emitter } from 'strict-event-emitter'
 
-interface EventsMap {
-  ping: (n: number) => void
+// Define a strict events contract where keys
+// represent event names and values represent
+// the list of arguments expected in ".emit()".
+type Events = {
+  ping: [number]
 }
 
-const emitter = new StrictEventEmitter<EventsMap>()
+const emitter = new Emitter<Events>()
 emitter.addListener('ping', (n) => {
@@ -37,7 +42,7 @@ // "n" argument type is inferred as "number'.
 emitter.emit('ping', 10) // OK
-emitter.emit('ping', 'wait, not a number') // TypeError
-emitter.emit('unknown', 10) // TypeError
+emitter.emit('unknown', 10) // TypeError (invalid event name)
+emitter.emit('ping', 'wait, not a number') // TypeError (invalid data)
 ```
 
-This library is a superset class of the native `EventEmitter` with only the type definition logic attached. There's no additional functionality present.
+This library is also a custom `EventEmitter` implementation, which makes it compatible with other environments, like browsers or React Native.
 
@@ -55,14 +60,14 @@ ## Getting started
 ```ts
-import { StrictEventEmitter } from 'strict-event-emitter'
+import { Emitter } from 'strict-event-emitter'
 
 // 1. Define an interface that describes your events.
-// Set event names as the keys, and their listner functions as the values.
-interface EventsMap {
-  connect: (id: string) => void
-  disconnect: (id: string) => void
+// Set event names as the keys, and their expected payloads as values.
+interface Events {
+  connect: [id: string]
+  disconnect: [id: string]
 }
 
-// 2. Create a strict emitter and pass the previously defined "EventsMap"
+// 2. Create a strict emitter and pass the previously defined "Events"
 // as its first generic argument.
-const emitter = new StrictEventEmitter<EventsMap>()
+const emitter = new Emitter<Events>()
 
@@ -69,0 +74,0 @@ // 3. Use the "emitter" the same way you'd use the regular "EventEmitter" instance.

New alerts

Major refactor

Supply chain risk

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

Found 1 instance in 1 package

Improved metrics

Total package byte prevSize

19274

increased by119.32%

Number of package files

12

increased by50%

Lines of code

401

increased by199.25%

Number of lines in readme file

80

increased by6.67%

Worsened metrics

Dev dependency count

9

increased by12.5%

Number of medium supply chain risk alerts

1

increased byInfinity%

No dependency changes