calls() does not return calls made from exception handler

[chafey]

Checklist

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

Bug description

I am writing an integration test that uses two mocked clients. The call to the first mocked client rejects and the second mocked client is called from the catch handler for the call to the first mocked client. calls() on the second mocked client returns an empty array even though the second mocked client was indeed called. I am expecting calls() to return a non empty array for the second mocked client.

Reproduction

import { mockClient } from "aws-sdk-client-mock";
import { GetObjectCommand, S3Client } from "@aws-sdk/client-s3";
import {
  PutMetricDataCommand,
  CloudWatchClient,
} from "@aws-sdk/client-cloudwatch";

const s3Client = new S3Client();
const s3ClientMock = mockClient(s3Client);
s3ClientMock.rejects("error");

const cloudWatchClient = new CloudWatchClient();
const cloudWatchClientMock = mockClient(cloudWatchClient);
cloudWatchClientMock.resolves({});

const input = {
  Namespace: "MyNamespace",
  MetricData: [
    {
      MetricName: "MyMetricName",
    },
  ],
};

describe("multiple mocked clients with one that throws", () => {
  test("calls() for both clients should return 1", async () => {
    s3ClientMock.reset();
    cloudWatchClientMock.reset();
    try {
      try {
        await s3Client.send(
          new GetObjectCommand({ Bucket: "foo", Key: "bar" })
        );
      } catch (e) {
        await cloudWatchClient.send(new PutMetricDataCommand(input));
        throw e;
      }
    } catch (e: any) {}

    expect(s3ClientMock.calls().length).toBe(1);
    expect(cloudWatchClientMock.calls().length).toBe(1); // fails, received is 0
  });
});

Environment

• Node version: v18.16.0
• Testing lib and version: Jest 29.7.0
• Typescript version: 10.9.1
• AWS SDK v3 Client mock version: 2.113.0
• AWS JS SDK libs and versions: "@aws-sdk/client-cloudwatch": "^3.533.0", "@aws-sdk/client-s3": "^3.470.0",

[m-radzikowski]

At the beginning of your test, you reset() both mocks. This resets them to the default behavior - returning undefined for any send() call. As a result, the first call to S3 Client succeeds and does not throw.

It's best practice to reset mocks before every test if you test for different behaviors. But then you need to specify behaviors after the reset. For example:

import {mockClient} from "aws-sdk-client-mock";
import {GetObjectCommand, S3Client} from "@aws-sdk/client-s3";
import {CloudWatchClient, PutMetricDataCommand} from "@aws-sdk/client-cloudwatch";

const s3Client = new S3Client();
const s3ClientMock = mockClient(s3Client);

const cloudWatchClient = new CloudWatchClient();
const cloudWatchClientMock = mockClient(cloudWatchClient);

const input = {
  Namespace: "MyNamespace",
  MetricData: [
    {
      MetricName: "MyMetricName",
    },
  ],
};

beforeEach(() => {
  s3ClientMock.reset();
  cloudWatchClientMock.reset();
})

describe("multiple mocked clients with one that throws", () => {
  test("calls() for both clients should return 1", async () => {
    s3ClientMock.rejects("error");
    cloudWatchClientMock.resolves({});

    try {
      try {
        await s3Client.send(
          new GetObjectCommand({Bucket: "foo", Key: "bar"}),
        );
        console.log("s3Client.send success");
      } catch (e) {
        await cloudWatchClient.send(new PutMetricDataCommand(input));
        throw e;
      }
    } catch (e: any) {
    }

    expect(s3ClientMock.calls().length).toBe(1);
    expect(cloudWatchClientMock.calls().length).toBe(1); // fails, received is 0
  });
});