🚀 Feature Request: wrangler init should also generate an example test

[rozenmd]

Describe the solution

Just a test that index.ts/index.js returns "Hello World!" as expected

This should probably be an option as part of the init flow, you actually have to do a bunch of stuff to get Jest working:

For TypeScript

npm i -D jest babel-jest @babel/core @babel/preset-env @babel/preset-typescript @types/jest

• add "test": "jest" to package.json scripts
• create a babel.config.js (if babel.config.js already exists, let the user know to add "@babel/preset-typescript" to the presets array):

//babel.config.js
module.exports = {
  presets: [
    ["@babel/preset-env", { targets: { node: "current" } }],
    "@babel/preset-typescript",
  ],
};

• add @types/jest to the types array in tsconfig.json

• add an index.test.ts:

//index.test.ts
import { unstable_dev } from 'wrangler'

describe("worker", () => {
	it("should return Hello World", async () => {
		const worker = await unstable_dev(
			"src/index.ts",
			{},
			{ disableExperimentalWarning: true }
		);
		const resp = await worker.fetch();
		if (resp) {
			const text = await resp.text();
			expect(text).toMatchInlineSnapshot(`"Hello World!"`);
		}
		await worker.stop();
	});
});

Additional test runners to implement:

• Ava
• Mocha
• vitest

[petebacondarwin]

This is a great idea. I love that it actually tests the initial behaviour, which will break once people start changing the Worker. We have discussed if Jest is the runner we want to use; probably we might offer a selection?

[Skye-31]

+1 To offering choices between multiple tests suites, would be nice to at least include Ava & Mocha.

[rozenmd]

Un-assigning myself as I've got plenty of stuff to focus on - feel free to ask questions if you want to pick this up!

[JacobMGEvans]

Ooooh Vitest! I like that idea 😄

[JacobMGEvans]

+1 To offering choices between multiple tests suites, would be nice to at least include Ava & Mocha.

@Skye-31 Could consider those, since they are also major commonly used runners/suites

[penalosa]

We'll address this as part of the upcoming work on Miniflare's unit testing environment cc @admah @mrbbot

[admah]

The "Hello World" Worker templates (JS and TS) generated via C3 now include @cloudflare/vitest-pool-workers and an example test.

Closed by #5189