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I'm trying to unit test a function that returns a promise. I'm having challenges verifying if the mocked functions are called. Here's what I've done.,

// codetotest.js
const { SomeModule, isSomething, isSomethingElse } = require("some-module");
exports.somefunction = (param1, param2)=> {
    const someModule = new SomeModule();
    someModule.someMethod("aaa", isSomething);
    someModule.someMethod("bbb", isSomethingElse);
    return (someModule.someOtherMethod(param1)
    .then(()=>{someModule.run(param2)}));
And this is the test file, the test says the mocked functions are not called, but I do see the console statement in the mock function is being displayed.
// codetotest.test.js
const { somefunction} = require("./codetotest.js");
const { SomeModule } = require("some-module");
jest.mock("some-module", () => {
    return {
        SomeModule: jest.fn().mockImplementation(() => {
            return {
                someMethod: jest.fn((param, fn) => { console.log("This prints!"); }),
                someOtherMethod: jest.fn((param) => { return Promise.resolve(() => { }) }),
                run: jest.fn((param) => { return Promise.resolve(() => { return []; }) })
afterEach(() => {
    jest.resetAllMocks();
    jest.restoreAllMocks();
describe("Test codetotest.js", () => {
    it("somefunction() - success", async () => {
        const someModule = new SomeModule();
        let output = await somefunction("param1", "param2");
        expect(SomeModule).toHaveBeenCalled();
        expect(someModule.someMethod).toHaveBeenCalled(); // This fails
        await expect(someModule.someOtherMethod.mock.results[0]).resolves;
        expect(someModule.someOtherMethod).toHaveBeenCalled(); // This fails
        await expect(someModule.run.mocks.results[0]).resolves;
        expect(someModule.run).toHaveBeenCalled(); // This fails
Appreciate any help/pointers.
Thank you.
P.S: I'm still a beginner when it comes to nodeJs development and unit testing.
I spent quite some time on this and finally figured the instantiated mock class didn't return the mocked methods properly. This answer gave me a hint on where I was going wrong.
So accordingly, I had to change my test file as follows.,
// codetotest.test.js
const { somefunction} = require("./codetotest.js");
const { SomeModule } = require("some-module");
jest.mock("some-module", function() {
    return {
        SomeModule: jest.fn().mockImplementation(function() { // Arrow function cannot be used as constructor
            // Because I was not using the 'this' operator, my constructor always returned empty
            this.someMethod = jest.fn((param, fn) => { console.log("This prints!"); });
            this.someOtherMethod = jest.fn((param) => { return Promise.resolve(() => { }) });
            this.run = jest.fn((param) => { return Promise.resolve(() => { return []; }) });
            return {
                someMethod: this,someMethod,
                someOtherMethod: this.someOtherMethod,
                run: this.run
afterEach(() => {
    jest.restoreAllMocks();
describe("Test codetotest.js", () => {
    it("somefunction() - success", async () => {
        await somefunction("param1", "param2");
        expect(SomeModule).toHaveBeenCalled();
        expect(SomeModule.mock.instances[0].someMethod).toHaveBeenCalled(); // This works
        expect(SomeModule.mock.instances[0].someOtherMethod).toHaveBeenCalled(); // This works
        expect(someModule.mock.instances[0].run).toHaveBeenCalled(); // This works
        
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