Questions

• What is the correct/acceptable way to access all JavaScript/TypeScript functions in a module for unit testing?
• Is there a (good) reason why I shouldn't just export all my functions?

Context

Please forgive my ignorance; I have spent the majority of my professional career writing Python code using the Test Driven Development (TDD) approach. Now, I am finding myself learning ReactJS/TypeScript and figuring out how to implement unit tests, but I quickly found out that functions are only accessible if you export them. As most of you know, Python is very permissive; there really is no concept of privacy, so it's just a matter of importing the module and being respectful of what you have access to. But JavaScript only imports the functions of a module that have been explicitly exported, thus providing a modest barrier.

I've been told that it's not a great idea to export all my functions for testing, but I'm not aware of another way to actually be able to test them.

Examples

What I've been told is "correct/better":

Sample1.js:

const func1 = () => {
    //code that does stuff
    return "stuff";
};

const func2 = () => {
   //code that does other stuff
   return "otherStuff";
};

export { func1 };

Sample1.test.js:

// executed via Jest framework

import * as sample from "./Sample1.js"

describe("Unit Tests for Sample1", () => {
    test("Unit Test - func1", () => {
        // code that tests stuff
    };

    test("Unit Test - func2", () => {
        // can't test func2 because it's not exported
    };
};

What I'm doing to be able to test all functions:

Sample2.js:

const func1 = () => {
    //code that does stuff
    return "stuff";
};

const func2 = () => {
   //code that does other stuff
   return "otherStuff";
};

export { func1, func2 };

Sample2.test.js:

// executed via Jest framework

import * as sample from "./Sample2.js"

describe("Unit Tests for Sample2", () => {
    test("Unit Test - func1", () => {
        // code that tests stuff
    };

    test("Unit Test - func2", () => {
        // code that tests other stuff because it's exported
    };
};

For the Record

I've looked around on the internet and Stack Overflow specifically for standards and best practices, but I haven't found much that answers this specific question. The closest I found was this SO question, but it's not really what I'm after.