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unstable_startWorker()

note: we recommend using vitest

Wrangler's unstable_startWorker() API

If you do not want to use Vitest and would like to write integration tests for a single Worker, consider using Wrangler's unstable_startWorker() API. This API exposes the internals of Wrangler's dev server, and allows you to customise how it runs.

import assert from "node:assert";
import { unstable_startWorker } from "wrangler";


const worker = await unstable_startWorker({ config: "wrangler.json" });
try {
  const response = await worker.fetch("/?a=1&b=2");
  assert.strictEqual(await response.text(), "3");
} finally {
  await worker.dispose();
}