I'm using SinonJS, Mocha and chai for my unit tests.
I want to know if it's possible to mock the value of a variable or the return of a function with Sinon.

Imagine I have this:

testeA.ts

const getA = () => 20

export function test() {
  const valA = getA();
  const result = valA * 2; 
  return result;
}

Is it possible to mock the value returned by getA() and/or valA value inside my tests? Maybe use the mock instead of the actual method.

myTest.spec.ts

import * as test from './testeA'
import * as chai from 'chai'
import * as sinon from 'sinon'

const expect = chai.expect

describe('First Test', () => {
  it('should run the test', () => {    
    const myMock = sinon.mock('test') // Mock the function

    // MOck the values somehow
 
    
    expect(test.test()).to.be.equal(30)
  })
})