Fizz Buzz quiz with clean code and TDD

fizzBuzz.js

/**
 * Runner
 */

main();

/**
 * Program with Clean Code
 */

function main() {
  const result = program({ 3: "Fizz", 5: "Buzz", 7: "Bang" }, 100);
  result.forEach((element) => {
    console.log(element);
  });
}

function program(obj, num) {
  let result = [];
  for (let i = 1; i <= num; i++) {
    let element = "";
    Object.keys(obj).forEach((key) => {
      if (i % key === 0) {
        element += obj[key];
      }
    });
    result.push(element || i);
  }
  return result;
}

/**
 * Test Driven Development
 */

global.testProgram = () => {
  const result = program(
    { 3: "Fizz", 5: "Buzz", 7: "Bang" },
    lcm(3, 5, 7) + 10
  );
  result.unshift(null); // Increment the array index for convenience

  // Least common multiples
  assert(
    result[lcm(3, 5, 7)],
    "FizzBuzzBang",
    `lcm(3, 5, 7) give FizzBuzzBang`
  );
  assert(result[lcm(5, 7)], "BuzzBang", `lcm(5, 7) give BuzzBang`);
  assert(result[lcm(3, 7)], "FizzBang", `lcm(3, 7) give FizzBang`);
  assert(result[lcm(3, 5)], "FizzBuzz", `lcm(3,5) give FizzBuzz`);
  // Plain numbers
  assert(result[7], "Bang", "7 give Bang");
  assert(result[5], "Buzz", "5 give Buzz");
  assert(result[3], "Fizz", "3 give Fizz");
  assert(result[4], 4, "4 give 4");
  assert(result[2], 2, "2 give 2");
};

/**
 * Utils
 */

function test() {
  const testFunctions = {};
  const globalObject = typeof window === "undefined" ? global : window;
  Object.keys(globalObject).forEach((key) => {
    if (
      key.startsWith("test") &&
      key !== "test" &&
      typeof globalObject[key] === "function"
    ) {
      testFunctions[key] = globalObject[key];
    }
  });

  console.log("\n---");
  console.log("Testing");
  console.log("---");

  this.totalsExecuted = 0;
  this.totalsPassed = 0;
  this.suitesExecuted = 0;
  this.suitesPassed = 0;

  Object.keys(testFunctions).forEach((name) => {
    const testFunc = testFunctions[name];
    this.executed = 0;
    this.passed = 0;

    console.log(`• ${name.replace("test", "")}`);

    try {
      testFunc();
    } catch (e) {
      console.log("ERROR");
      console.error(e);
    }

    this.totalsExecuted += this.executed;
    this.totalsPassed += this.passed;
    this.suitesExecuted++;
    if (this.executed === this.passed) {
      this.suitesPassed++;
    }

    console.log(`  Tests: ${passed} passed, ${executed} total`);
  });
  console.log("---");
  console.log(`Tests: ${totalsPassed} passed, ${totalsExecuted} total`);
  console.log(`Test Suites: ${suitesPassed} passed, ${suitesExecuted} total`);
  console.log("---");
}

function assert(result, expectedOutput, expectedMessage) {
  this.executed++;
  if (result !== expectedOutput) {
    console.error(`    ✘  Assert ${expectedMessage}`);
    return false;
  }
  this.passed++;
  console.log(`    √  Assert ${expectedMessage}`);
  return true;
}

function lcm(...numbers) {
  if (numbers.length === 0) return;

  let result = numbers[0];
  for (let i = 1; i < numbers.length; i++) {
    result = (result * numbers[i]) / gcd(result, numbers[i]);
  }
  return result;
}

function gcd(a, b) {
  if (b === 0) return a;
  return gcd(b, a % b);
}

/**
 * Test Runner
 */

test();

Write a program, using clean code principles and TDD (Test Driven Development), that prints the numbers from 1 to 100. But for multiples of 3 print “Fizz” instead of the number and for the multiples of 5 print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz “. Make it also extendible adding 7 that print Bang.

Code wthout a solution:

/**
 * Runner
 */

main();

/**
 * Program with Clean Code
 */

function main() {
  // your code ...
}

/**
 * Test Driven Development
 */

global.testProgram = () => {
  // add your test assert using `assert(true, true, "description")`
}

/**
 * Utils
 */

function test() {
  const testFunctions = {};
  const globalObject = typeof window === "undefined" ? global : window;
  Object.keys(globalObject).forEach((key) => {
    if (
      key.startsWith("test") &&
      key !== "test" &&
      typeof globalObject[key] === "function"
    ) {
      testFunctions[key] = globalObject[key];
    }
  });

  console.log("\n---");
  console.log("Testing");
  console.log("---");

  this.totalsExecuted = 0;
  this.totalsPassed = 0;
  this.suitesExecuted = 0;
  this.suitesPassed = 0;

  Object.keys(testFunctions).forEach((name) => {
    const testFunc = testFunctions[name];
    this.executed = 0;
    this.passed = 0;

    console.log(`• ${name.replace("test", "")}`);

    try {
      testFunc();
    } catch (e) {
      console.log("ERROR");
      console.error(e);
    }

    this.totalsExecuted += this.executed;
    this.totalsPassed += this.passed;
    this.suitesExecuted++;
    if (this.executed === this.passed) {
      this.suitesPassed++;
    }

    console.log(`  Tests: ${passed} passed, ${executed} total`);
  });
  console.log("---");
  console.log(`Tests: ${totalsPassed} passed, ${totalsExecuted} total`);
  console.log(`Test Suites: ${suitesPassed} passed, ${suitesExecuted} total`);
  console.log("---");
}

function assert(result, expectedOutput, expectedMessage) {
  this.executed++;
  if (result !== expectedOutput) {
    console.error(`    ✘  Assert ${expectedMessage}`);
    return false;
  }
  this.passed++;
  console.log(`    √  Assert ${expectedMessage}`);
  return true;
}

function lcm(...numbers) {
  if (numbers.length === 0) return;

  let result = numbers[0];
  for (let i = 1; i < numbers.length; i++) {
    result = (result * numbers[i]) / gcd(result, numbers[i]);
  }
  return result;
}

function gcd(a, b) {
  if (b === 0) return a;
  return gcd(b, a % b);
}

/**
 * Test Runner
 */

test();