Custom Jest matchers not working with Typescript

[andrewh318]

Checklist

• I have read Caveats documentation and didn't find a solution for this problem there.

Bug description

The custom Jest matchers don't seem to be properly supported with Typescript. I'm getting the following error when trying to use toHaveReceivedCommand. Note that I'm using import 'aws-sdk-client-mock-jest' as per the documentation.

Property 'toHaveReceivedCommand' does not exist on type 'Matchers<void, AwsStub<ServiceInputTypes, ServiceOutputTypes, S3ClientResolvedConfig>> & SnapshotMatchers<...> & Inverse<...> & PromiseMatchers<...>'

When I @ts-ignore the line the matcher works fine, so it seems like a typing issue? (for the expect call?). Is there any additional configuration required to get the matchers set up for Typescript?

Reproduction

import { describe, it, expect, beforeEach } from '@jest/globals';
import { PutObjectAclCommand, S3Client } from '@aws-sdk/client-s3';
import { mockClient } from 'aws-sdk-client-mock';
import 'aws-sdk-client-mock-jest';

describe('example', () => {
    const s3Mock = mockClient(S3Client);

    beforeEach(() => {
        s3Mock.reset();
    });
    it('test', async () => {
        // Property 'toHaveReceivedCommand' does not exist on type 'Matchers<void, AwsStub<ServiceInputTypes, ServiceOutputTypes, S3ClientResolvedConfig>> & SnapshotMatchers<...> & Inverse<...> & PromiseMatchers<...>'`
        expect(s3Mock).toHaveReceivedCommand(PutObjectAclCommand);
    });
});

Environment

• Node version: 16.14.0
• Testing lib and version: Jest
• Typescript version: 5.0.4
• AWS SDK v3 Client mock version: 3.0.0
• AWS JS SDK libs and versions:
  • @aws-sdk/client-s3": "3.387.0"

[mx0c]

same here :(

[Tanemahuta]

Try this:

import * as matchers from 'aws-sdk-client-mock-jest';

describe("blubb", () => {
  expect.extend(matchers);
});

Be happy.

[mx0c]

still doesn't seem to work:

[samchungy]

The import modifies the global types which are only available when you install @types/jest

[orien]

It would be awesome if it worked without using @types/jest. Jest now provides its own types via @jest/globals, as is used in the code block supplied with this issue.

[orien]

A work around is to redeclare the matcher functions. ie. copy those in use from https://github.com/m-radzikowski/aws-sdk-client-mock/blob/v3.0.0/packages/aws-sdk-client-mock-jest/src/jestMatchers.ts#L7-L70

  import { describe, it, expect, beforeEach } from '@jest/globals';
  import { PutObjectAclCommand, S3Client } from '@aws-sdk/client-s3';
- import { mockClient } from 'aws-sdk-client-mock';
+ import { MetadataBearer } from '@smithy/types'
+ import { AwsCommand, mockClient } from 'aws-sdk-client-mock';
  import 'aws-sdk-client-mock-jest';

+ declare module 'expect' {
+   interface Matchers<R> {
+     toHaveReceivedCommand<TCmdInput extends object, TCmdOutput extends MetadataBearer>
+       (command: new (input: TCmdInput) => AwsCommand<TCmdInput, TCmdOutput>): R;
+   }
+ }

  describe('example', () => {
      const s3Mock = mockClient(S3Client);

      beforeEach(() => {
          s3Mock.reset();
      });
      it('test', async () => {
          expect(s3Mock).toHaveReceivedCommand(PutObjectAclCommand);
      });
  });

[adiktofsugar]

They solved this with testing-library in definitely typed like this: DefinitelyTyped/DefinitelyTyped#65981

I fixed in a similar way by adding to custom.d.ts:

import type { AwsSdkJestMockMatchers } from 'aws-sdk-client-mock-jest/dist/types/jestMatchers';

declare module 'expect' {
    interface Matchers<R = void, T = {}> extends AwsSdkJestMockMatchers<R> {}
}

It would be nice if that was just in the package, though.

EDIT: this seemed to have fixed the problem but apparently it was just VSCode fooling me. I expect something like this would work, though.

[m-radzikowski]

I've migrated to using @jest/globals types in Jest matcher definition, along with adding type definition for expect lib using under the hood. Now, matchers should work with both @types/jest and @jest/globals expect().

Released in v3.1.0-beta.0. Please test it if you have a moment.

[nmussy]

Hey @m-radzikowski, thanks for attempting to fix this, but it's still not working for me, neither for 3.1.0-beta.0 nor 3.1.0-beta.1. Let me know if I'm doing something wrong here:

import {
	DescribeDBEngineVersionsCommand,
	RDSClient,
} from "@aws-sdk/client-rds";
import { beforeEach, expect, it } from "@jest/globals";
import { mockClient } from "aws-sdk-client-mock";
import "aws-sdk-client-mock-jest";

const rdsMock = mockClient(RDSClient);

beforeEach(() => {
	rdsMock.reset();
});

it("demo", async () => {
	expect(rdsMock).toHaveReceivedCommand(DescribeDBEngineVersionsCommand);
});

package.json:

  "devDependencies": {
    "@jest/globals": "^29.7.0",
    "@types/node": "^20.11.24",
    "aws-sdk-client-mock": "3.1.0-beta.1",
    "aws-sdk-client-mock-jest": "^3.0.1",
    "esbuild": "^0.20.1",
    "esbuild-jest": "^0.5.0",
    "jest": "^29.7.0",
    "typescript": "^5.3.3"
  },
  "dependencies": {
    "@aws-sdk/client-rds": "^3.525.0"
  }

I get the following type error:

Property 'toHaveReceivedCommand' does not exist on type 'Matchers<void, AwsStub<object, MetadataBearer, unknown>> & SnapshotMatchers<void, AwsStub<object, MetadataBearer, unknown>> & Inverse<JestMatchers<void, AwsStub<object, MetadataBearer, unknown>>> & PromiseMatchers<...>'.ts(2339)

I've also tried to expect.extend(matchers);, to no avail

[m-radzikowski]

@nmussy you need to update aws-sdk-client-mock-jest to 3.1.0-beta.1 as well. Then your code works fine for me.

[nmussy]

That was my issue, thanks 👍
For reference, here is the corrected package.json dependencies:

  "devDependencies": {
    "@jest/globals": "^29.7.0",
    "@types/node": "^20.11.24",
    "aws-sdk-client-mock": "3.1.0-beta.1",
    "aws-sdk-client-mock-jest": "3.1.0-beta.1",
    "esbuild": "^0.20.1",
    "esbuild-jest": "^0.5.0",
    "jest": "^29.7.0",
    "typescript": "^5.3.3"
  },
  "dependencies": {
    "@aws-sdk/client-rds": "^3.525.0"
  }

[adiktofsugar]

3.1.0-beta.1 in both packages worked for me too. Thanks!