Testing Private Functions: Basic

cats.js

function createFunnyName(name) {
  return `^^${name}^^`;
}

module.exports = {
  createCat(name) {
    return {
      name: name,
      funnyName: createFunnyName(name)
    };
  }
};

index.js

const catCreator = require('./modules/cats');

const zelda = catCreator.createCat('Zelda');
console.log(zelda); // { name: 'Zelda', funnyName: '^^Zelda^^' }

const frida = catCreator.createCat('Frida');
console.log(frida); // { name: 'Frida', funnyName: '^^Frida^^' }

test.js

const test = require("tape");
const catCreator = require("./modules/cats");

const name = "Zelda";

test("Should return an object", t => {
  t.equal(typeof catCreator.createCat(name), "object");
  t.end();
});

test("Cat name should be funny", t => {
  const result = catCreator.createCat(name).funnyName;

  t.equal(result, `^^${name}^^`, "Should contain ^^ before and after the name");
  t.ok(result.indexOf(name) === 2, "Should contain the name");
  t.end();
});