import { assertEquals, assertStrictEquals, fail,} from "https://deno.land/std@0.127.0/testing/asserts.ts";
import { EventEmitter } from "./EventEmitter.ts";
type Events = Record<string, unknown> & { ping: undefined; pong: string; peng: { data: string };};
Deno.test("types of detail", () => { const emitter = new EventEmitter<Events>();
emitter.on("ping", (detail) => { console.log("ping: ", detail);
assertEquals(detail, undefined); });
emitter.emit("ping");
emitter.on("pong", (detail) => { console.log("pong: ", detail);
assertEquals(detail, "hello"); });
emitter.emit("pong", "hello");
emitter.on("peng", (detail) => { console.log("peng: ", detail);
assertEquals(detail.data, "peng emitted!"); });
emitter.emit("peng", { data: "peng emitted!", });});
Deno.test("on", () => { const ee = new EventEmitter<Events>();
ee.on("foo", (detail) => { assertEquals(detail, "bar"); });
ee.emit("foo", "bar");});
Deno.test("once", () => { const ee = new EventEmitter<Events>();
ee.once("pong", (detail) => { assertEquals(detail, "bar"); });
ee.emit("pong", "bar");});
Deno.test("off", () => { const ee = new EventEmitter<Events>();
function foo() { fail(); }
ee.on("foo", foo);
ee.off("foo", foo);
ee.emit("foo", "bar");});
Deno.test("offEvent", () => { const ee = new EventEmitter<Events>();
let i = 0;
ee.on("foo", () => i++);
ee.on("foo", () => i++);
ee.off();
ee.emit("foo", "bar");
assertEquals(i, 0);});
Deno.test("offAll", () => { const ee = new EventEmitter<Events>();
let i = 0;
ee.on("foo", () => i++);
ee.on("bar", () => i++);
ee.off();
ee.emit("foo", "bar");
assertEquals(i, 0);});
Deno.test("chainable", () => { const ee = new EventEmitter<Events>();
function foo() { fail(); }
ee .on("foo", foo) .off("foo", foo);
ee.emit("foo", "bar");});
Deno.test("extend", () => { class Extending extends EventEmitter<Events> { foo() { this.emit("pong", "pong"); } }
const ext = new Extending();
ext.on("pong", (detail) => { assertEquals(detail, "pong"); });
ext.foo();
ext.emit("pong", "pong");});
Deno.test("extend with custom events", () => { class Extending extends EventEmitter<Events> { foo() { this.emit("pong", "pong"); } }
const ext = new Extending();
ext.on("pong", (detail) => { assertEquals(detail, "pong"); });
ext.foo();
ext.emit("pong", "pong");});
Deno.test("pub / sub", () => { const ee = new EventEmitter<Events>();
const cleanup = ee.subscribe("pong", (detail) => { assertEquals<string>(detail, "hello"); });
ee.emit("pong", "hello");
cleanup();
const cleanup2 = ee.subscribe("peng", (detail) => { assertEquals<string>(detail.data, "hello"); });
ee.emit("peng", { data: "hello", });
cleanup2();});
Deno.test("getListeners", () => { const ee = new EventEmitter<Events>();
const cb1 = () => {};
const cb2 = () => {};
ee.on("pong", cb1);
ee.addEventListener("pong", cb2);
ee.addEventListener("ping", () => {});
let listeners = ee.getListeners();
assertEquals(listeners.size, 2);
assertEquals(listeners.get("pong")!.size, 2);
assertEquals(listeners.get("ping")!.size, 1);
ee.off("ping");
listeners = ee.getListeners();
assertEquals(listeners.size, 1);
assertEquals(listeners.get("pong")!.size, 2);
assertEquals(listeners.get("ping"), undefined);
ee.off("pong", cb1);
listeners = ee.getListeners();
assertEquals(listeners.get("pong")!.size, 1);
ee.off();
listeners = ee.getListeners();
console.log(listeners);
assertEquals(listeners.size, 0);});
Deno.test("EventEmitter.createEvent", async (ctx) => { await ctx.step("created event has correct property values", () => { const eventType = "name"; const eventDetail = { string: "", number: NaN }; const ev = EventEmitter.createEvent(eventType, eventDetail);
ev.type === eventType; ev.detail === eventDetail;
assertStrictEquals(ev.type, eventType); assertStrictEquals(ev.detail, eventDetail); });});
Deno.test("EventEmitter", async (ctx) => { type CountMap = { adjustCount: "increment" | "decrement" };
await ctx.step("dispatches events", () => { const target = new EventEmitter<CountMap>(); let count = 0;
target.addEventListener("adjustCount", ({ detail }) => { count += detail === "increment" ? 1 : -1; });
const incrementEvent = EventEmitter.createEvent( "adjustCount", "increment" as const, );
target.dispatchEvent(incrementEvent);
target.dispatchEvent(incrementEvent);
target.dispatch("adjustCount", "decrement");
target.dispatch("adjustCount", "decrement");
target.dispatch("adjustCount", "increment");
assertStrictEquals(count, 1); });
await ctx.step('correctly implements "once" option', () => { const target = new EventEmitter<CountMap>(); let count = 0;
const cb = (ev: CustomEvent<CountMap["adjustCount"]>) => { count += ev.detail === "increment" ? 1 : -1; };
target.addEventListener("adjustCount", cb, { once: true });
const incrementEvent = EventEmitter.createEvent( "adjustCount", "increment" as const, );
assertStrictEquals(count, 0);
target.dispatchEvent(incrementEvent);
assertStrictEquals(count, 1);
target.dispatchEvent(incrementEvent);
assertStrictEquals(count, 1); });
await ctx.step('"subscribe" method returns "unsubscribe" function', () => { const target = new EventEmitter<CountMap>();
let count = 0;
const unsubscribe = target.subscribe("adjustCount", (payload) => { count += payload === "increment" ? 1 : -1;
unsubscribe(); });
assertStrictEquals(count, 0);
target.publish("adjustCount", "increment");
assertStrictEquals(count, 1);
target.publish("adjustCount", "increment");
assertStrictEquals(count, 1); });});