code-server/test/unit/common/emitter.test.ts
2021-07-29 09:48:40 -07:00

93 lines
2.6 KiB
TypeScript

// Note: we need to import logger from the root
// because this is the logger used in logError in ../src/common/util
import { logger } from "@coder/logger"
import { Emitter } from "../../../src/common/emitter"
describe("emitter", () => {
let spy: jest.SpyInstance
beforeEach(() => {
spy = jest.spyOn(logger, "error")
})
afterEach(() => {
jest.clearAllMocks()
})
afterAll(() => {
jest.restoreAllMocks()
})
it("should run the correct callbacks", async () => {
const HELLO_WORLD = "HELLO_WORLD"
const GOODBYE_WORLD = "GOODBYE_WORLD"
const mockCallback = jest.fn(() => "Mock function called")
const mockSecondCallback = jest.fn(() => undefined)
const emitter = new Emitter<{ event: string; callback: () => void }>()
const onHelloWorld = ({ event, callback }: { event: string; callback: () => void }): void => {
if (event === HELLO_WORLD) {
callback()
}
}
const onGoodbyeWorld = ({ event, callback }: { event: string; callback: () => void }): void => {
if (event === GOODBYE_WORLD) {
callback()
}
}
// Register the onHelloWorld listener
// and the onGoodbyeWorld
const _onHelloWorld = emitter.event(onHelloWorld)
emitter.event(onGoodbyeWorld)
await emitter.emit({ event: HELLO_WORLD, callback: mockCallback })
// Double-check that our callback is called only once
expect(mockCallback).toHaveBeenCalled()
expect(mockCallback).toHaveBeenCalledTimes(1)
await emitter.emit({ event: GOODBYE_WORLD, callback: mockSecondCallback })
// Check that it works with multiple listeners
expect(mockSecondCallback).toHaveBeenCalled()
expect(mockSecondCallback).toHaveBeenCalledTimes(1)
// Dispose of individual listener
_onHelloWorld.dispose()
// Try disposing twice
_onHelloWorld.dispose()
// Dispose of all the listeners
emitter.dispose()
})
it("should log an error if something goes wrong", async () => {
const HELLO_WORLD = "HELLO_WORLD"
const mockCallback = jest.fn(() => "Mock function called")
const message = "You don't have access to that folder."
const emitter = new Emitter<{ event: string; callback: () => void }>()
const onHelloWorld = ({ event, callback }: { event: string; callback: () => void }): void => {
if (event === HELLO_WORLD) {
callback()
throw new Error(message)
}
}
emitter.event(onHelloWorld)
await emitter.emit({ event: HELLO_WORLD, callback: mockCallback })
// Check that error was called
expect(spy).toHaveBeenCalled()
expect(spy).toHaveBeenCalledTimes(1)
expect(spy).toHaveBeenCalledWith(message)
})
})