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

```ts
function assertRejectsSame(
  promise: PromiseLike<unknown>,
  expected: unknown,
): Promise<void>;
```

Defined in: [packages/common/src/Assert.ts:593](https://github.com/evoluhq/evolu/blob/ecbac001e0c18bbc45b44715f49ecc3a768c5ec9/packages/common/src/Assert.ts#L593)

Asserts that a promise rejects with the same value using `Object.is`.

Use this to verify that a rejection reason was propagated unchanged. For
value comparisons, use [assertRejects](https://evolu.dev/docs/api-reference/common/Assert/functions/assertRejects).

### Example

```ts

const expected = new Error("Unavailable.");
await assertRejectsSame(Promise.reject(expected), expected);
```