Test.js

const assert = require('assert');

const GREEN = '\x1b[32m';
const RED = '\x1b[31m';
const WHITE = '\x1b[37m';

class Test {
  constructor() {
    this.failures = [];
    this.count = 0;
  }

  printFailure(failure) {
    console.error(`${RED}
  ❌  FAILURE: ${failure}`);
  }

  printSuccess(success) {
    console.log(`${GREEN}
  ✅  SUCCESS: ${success}`);
  }

  printSection(section) {
    console.log(`${WHITE}

${'-'.repeat(section.length + 4)}
  ${section}
${'-'.repeat(section.length + 4)}`);
  }


  printFailed() {
    console.error(`${RED}

  ${this.failures.length} tests failed (out of ${this.count} tests total)`);
  }

  printPassed() {
    console.log(`${GREEN}

  🎉  All tests passed! (${this.count} tests total) 🎉`);
  }

  run(func, io = []) {
    const successes = [];
    const testFailures = []

    io.forEach(([input, expected, message = '', spread], i) => {
      this.count++;

      let result;

      if (spread) {
        result = func(...input);
      } else {
        result = func(input);
      }

      try {
        assert.deepEqual(
          result,
          expected,
          `[${func.name}] (${i + 1}) Expected "${result}" to equal "${expected}": ${message}`
        );

        successes.push(`${func.name} (${message})`);

      } catch (e) {
        testFailures.push(e);
      }
    });

    this.printSection(func.name);

    if (successes) {
      successes.forEach(this.printSuccess);
    }

    if (testFailures.length) {
      testFailures.forEach(this.printFailure);
    }

    this.failures = this.failures.concat(testFailures);
  }

  result() {
    if (this.failures.length) {
      this.printSection('TEST FAILURES');

      this.failures.forEach(this.printFailure);

      printFailed();

      process.exit(1);
    }

    return this.printPassed();
  }
}

module.exports = Test;