The Journey of #100DaysOfCode (@sourabhbagrecha)

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#Day95 of #100daysofcode

Today I learned about Testing in JavaScript. Also, I learned how to implement my own testing framework by following this JavaScript testing guide by Kent C Dodds:
Here’s my implementation of my very basic not-at-all-production-ready testing framework:

const {sum, subtract} = require('./math')

test('sum adds numbers', () => {
  const result = sum(3, 7)
  const expected = 10
  expect(result).toBe(expected)
})

test('subtract subtracts numbers', () => {
  const result = subtract(7, 3)
  const expected = 4
  expect(result).toBe(expected)
})

function test(title, callback) {
  try {
    callback()
    console.log(`✓ ${title}`)
  } catch (error) {
    console.error(`✕ ${title}`)
    console.error(error)
  }
}

function expect(actual) {
  return {
    toBe(expected) {
      if (actual !== expected) {
        throw new Error(`${actual} is not equal to ${expected}`)
      }
    },
  }
}

Testing tools like Jest provide expect & test functions out of the box along with some really productive CLI tooling.

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