chore: extract event-emitter from core

Signed-off-by: Jari Kolehmainen <jari.kolehmainen@gmail.com>

packages/core/src/common/__tests__/event-emitter.test.ts

@@ -1,86 +0,0 @@
-/**
- * Copyright (c) OpenLens Authors. All rights reserved.
- * Licensed under MIT License. See LICENSE in root directory for more information.
- */
-
-import { EventEmitter } from "../event-emitter";
-
-describe("EventEmitter", () => {
-  it("should stop early if a listener returns false", () => {
-    let called = false;
-    const e = new EventEmitter<[]>();
-
-    e.addListener(() => false, {});
-    e.addListener(() => { called = true; }, {});
-    e.emit();
-
-    expect(called).toBe(false);
-  });
-
-  it("shouldn't stop early if a listener returns 0", () => {
-    let called = false;
-    const e = new EventEmitter<[]>();
-
-    e.addListener(() => 0 as never, {});
-    e.addListener(() => { called = true; }, {});
-    e.emit();
-
-    expect(called).toBe(true);
-  });
-
-  it("prepended listeners should be called before others", () => {
-    const callOrder: number[] = [];
-    const e = new EventEmitter<[]>();
-
-    e.addListener(() => { callOrder.push(1); }, {});
-    e.addListener(() => { callOrder.push(2); }, {});
-    e.addListener(() => { callOrder.push(3); }, { prepend: true });
-    e.emit();
-
-    expect(callOrder).toStrictEqual([3, 1, 2]);
-  });
-
-  it("once listeners should be called only once", () => {
-    const callOrder: number[] = [];
-    const e = new EventEmitter<[]>();
-
-    e.addListener(() => { callOrder.push(1); }, {});
-    e.addListener(() => { callOrder.push(2); }, {});
-    e.addListener(() => { callOrder.push(3); }, { once: true });
-    e.emit();
-    e.emit();
-
-    expect(callOrder).toStrictEqual([1, 2, 3, 1, 2]);
-  });
-
-  it("removeListener should stop the listener from being called", () => {
-    const callOrder: number[] = [];
-    const e = new EventEmitter<[]>();
-    const r = () => { callOrder.push(3); };
-
-    e.addListener(() => { callOrder.push(1); }, {});
-    e.addListener(() => { callOrder.push(2); }, {});
-    e.addListener(r);
-
-    e.emit();
-    e.removeListener(r);
-    e.emit();
-
-    expect(callOrder).toStrictEqual([1, 2, 3, 1, 2]);
-  });
-
-  it("removeAllListeners should stop the all listeners from being called", () => {
-    const callOrder: number[] = [];
-    const e = new EventEmitter<[]>();
-
-    e.addListener(() => { callOrder.push(1); });
-    e.addListener(() => { callOrder.push(2); });
-    e.addListener(() => { callOrder.push(3); });
-
-    e.emit();
-    e.removeAllListeners();
-    e.emit();
-
-    expect(callOrder).toStrictEqual([1, 2, 3]);
-  });
-});

packages/core/src/common/app-event-bus/app-event-bus.injectable.ts

@@ -3,7 +3,7 @@
  * Licensed under MIT License. See LICENSE in root directory for more information.
  */
 import { getInjectable } from "@ogre-tools/injectable";
-import { EventEmitter } from "../event-emitter";
+import { EventEmitter } from "@k8slens/event-emitter";
 import type { AppEvent } from "./event-bus";
 
 const appEventBusInjectable = getInjectable({

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

@@ -1,43 +0,0 @@
-/**
- * Copyright (c) OpenLens Authors. All rights reserved.
- * Licensed under MIT License. See LICENSE in root directory for more information.
- */
-
-// Custom event emitter
-
-export interface EventEmitterOptions {
-  once?: boolean; // call once and remove
-  prepend?: boolean; // put listener to the beginning
-}
-
-export type EventEmitterCallback<D extends any[]> = (...data: D) => void | boolean;
-
-export class EventEmitter<D extends any[]> {
-  protected listeners: [EventEmitterCallback<D>, EventEmitterOptions][] = [];
-
-  addListener(callback: EventEmitterCallback<D>, options: EventEmitterOptions = {}) {
-    const fn = options.prepend ? "unshift" : "push";
-
-    this.listeners[fn]([callback, options]);
-  }
-
-  removeListener(callback: EventEmitterCallback<D>) {
-    this.listeners = this.listeners.filter(([cb]) => cb !== callback);
-  }
-
-  removeAllListeners() {
-    this.listeners.length = 0;
-  }
-
-  emit(...data: D) {
-    for (const [callback, { once }] of this.listeners) {
-      if (once) {
-        this.removeListener(callback);
-      }
-
-      if (callback(...data) === false) {
-        break;
-      }
-    }
-  }
-}

packages/core/src/common/k8s-api/json-api.ts

@@ -12,7 +12,7 @@ import type { Response, RequestInit } from "@k8slens/node-fetch";
 import { stringify } from "querystring";
 import type { Patch } from "rfc6902";
 import type { PartialDeep, ValueOf } from "type-fest";
-import { EventEmitter } from "../../common/event-emitter";
+import { EventEmitter } from "@k8slens/event-emitter";
 import type { Logger } from "../../common/logger";
 import type { Fetch } from "../fetch/fetch.injectable";
 import type { Defaulted } from "@k8slens/utilities";

packages/core/src/extensions/common-api/event-bus.ts

@@ -6,7 +6,7 @@
 import appEventBusInjectable from "../../common/app-event-bus/app-event-bus.injectable";
 import { asLegacyGlobalForExtensionApi } from "../as-legacy-globals-for-extension-api/as-legacy-global-object-for-extension-api";
 import type { AppEvent } from "../../common/app-event-bus/event-bus";
-import type { EventEmitter, EventEmitterCallback, EventEmitterOptions } from "../../common/event-emitter";
+import type { EventEmitter, EventEmitterCallback, EventEmitterOptions } from "@k8slens/event-emitter";
 
 export type {
   AppEvent,

packages/core/src/extensions/extension-loader/extension-loader.ts

@@ -14,7 +14,7 @@ import type { LensExtension } from "../lens-extension";
 import { extensionLoaderFromMainChannel, extensionLoaderFromRendererChannel } from "../../common/ipc/extension-handling";
 import { requestExtensionLoaderInitialState } from "../../renderer/ipc";
 import assert from "assert";
-import { EventEmitter } from "../../common/event-emitter";
+import { EventEmitter } from "@k8slens/event-emitter";
 import type { Extension } from "./extension/extension.injectable";
 import type { Logger } from "../../common/logger";
 import type { JoinPaths } from "../../common/path/join-paths.injectable";