Type error with Vitest matchers

[kyota-fujikura]

Checklist

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

Bug description

When using matchers for Vitest, TypeScript reports the following error:

error TS2339: Property 'toHaveReceivedCommandWith' does not exist on type 'Assertion<AwsStub<ServiceInputTypes, ServiceOutputTypes, CognitoIdentityProviderClientResolvedConfig>>'.

This happens despite correctly importing aws-sdk-client-mock-jest/vitest in the test files.

The error occurs under either of these conditions:

• When using ES modules ("type": "module" in package.json)
• When using CommonJS ("type": "commonjs" in package.json) and importing "aws-sdk-client-mock-jest/vitest" before importing "vitest"

Adding import "vitest" at the top of the vitest.d.ts file (in node_modules/aws-sdk-client-mock-jest) seems to fix the issue, which matches what's shown in the Vitest official documentation.
I'm not familiar enough with TypeScript's module mechanisms to understand why this fixes the issue.

Reproduction

package.json

{
  "type": "module",
  "dependencies": {
    "@aws-sdk/client-lambda": "^3.777.0",
    "aws-sdk-client-mock": "^4.1.0",
    "aws-sdk-client-mock-jest": "^4.1.0",
    "typescript": "^5.8.2",
    "vitest": "^3.0.9"
  },
  "pnpm": {
    "overrides": {
      // fix https://github.com/m-radzikowski/aws-sdk-client-mock/issues/243
      "chalk": "^5.4.0"
    }
  }
}

tsconfig.json

{
    "compilerOptions": {
        "target": "es2022",
        "lib": ["es2022"],
        "module": "node16",
        "esModuleInterop": true,
        "forceConsistentCasingInFileNames": true,
        "skipLibCheck": true,
        "types": ["vitest/globals"]
    },
    "include": ["src/**/*"]
}

vitest.config.ts

import { defineConfig } from "vitest/config";

export default defineConfig({
  test: {
    globals: true,
  },
});

test file

import "aws-sdk-client-mock-jest/vitest";
import { InvokeCommand, LambdaClient } from "@aws-sdk/client-lambda";
import { mockClient } from "aws-sdk-client-mock";
import "aws-sdk-client-mock-jest/vitest";

test("test", () => {
  const mockLambdaClient = mockClient(LambdaClient);

  // error occurs here
  expect(mockLambdaClient).toHaveReceivedCommand(InvokeCommand);
});

Environment

• Node version: v20.9.0
• Testing lib and version: vitest v3.0.9
• Typescript version: v5.8.2
• AWS SDK v3 Client mock version: v4.1.0
• AWS JS SDK libs and versions: @aws-sdk/client-lambda: v3.777.0

[jasonterando]

For anybody stumbling upon this, I got tests to run and matcher typings to work in VSCode by doing the following:

1. Add aws-sdk-client-mock-jest and chalk as development dependencies:
   npm install --save-dev chalk aws-sdk-client-mock-jest

2. In your test setup.ts, add the following to get types to work properly:

import 'aws-sdk-client-mock-jest';
import 'aws-sdk-client-mock-jest/vitest';
import 'aws-sdk-client-mock-vitest/extend';

[samchungy]

For anybody stumbling upon this, I got tests to run and matcher typings to work in VSCode by doing the following:

1. Add aws-sdk-client-mock-jest and chalk as development dependencies:
   `npm install --save-dev chalk aws-sdk-client-mock-jest`

2. In your test setup.ts, add the following to get types to work properly:

import 'aws-sdk-client-mock-jest';
import 'aws-sdk-client-mock-jest/vitest';
import 'aws-sdk-client-mock-vitest/extend';

Um aws-sdk-client-mock-vitest is a completely different library. You don't need the top 2 imports