[API reference](https://evolu.dev/docs/api-reference) › [@evolu/common](https://evolu.dev/docs/api-reference/common) › [Worker](https://evolu.dev/docs/api-reference/common/Worker) › testCreateSharedWorker

```ts
function testCreateSharedWorker<Input, Output>(): TestSharedWorker<
  Input,
  Output
>;
```

Defined in: [packages/common/src/Worker.ts:353](https://github.com/evoluhq/evolu/blob/e7144e2bbe9069362b62dec1b64a8aa922b8f1b0/packages/common/src/Worker.ts#L353)

Creates a connected [TestSharedWorker](https://evolu.dev/docs/api-reference/common/Worker/interfaces/TestSharedWorker) for testing.

The returned worker includes `self` and `connect` so tests can exercise the
full worker ↔ client pipeline without a real worker thread.