Vanilla JavaScript Test Harness Implementations for Fun and Profit. Never leave the house without one!

async_testing_harness_tape_api.js

// I like to start projects with a harness, so here is an async and a non-async harness
// compatible* to the tape api so they are easily portable
//
// *theres just 2 methods I normally use but you can add as many as you like
//

function test(name, f){
  
  test.run = test.run || false
  test.queue = test.queue || []

  test.queue.push(() => { 

    console.log(`Test: %c${name}`, 'color: violet')
    f({ end, ok }) 
  })


  if(test.run) return

  test.run = true
  setTimeout(end, 0) //wait until stack empty - so all tests have been added to queue

  
  /* Implement as many Tape Features as you like:
  */
  function end(){
    if(test.queue.length !== 0){ return test.queue.shift()() }

    test.run = false
    console.log("done.")
  }


  function ok(expr, msg){
      expr
      ? console.log(`%c:)   pass: ${msg}`, 'color: darkgreen')
      : console.log(`%c:(   fail: ${msg}`, 'color: red')
  }
}

test("init", function(t){
  t.ok(true, "okgo")   
  t.end()
})

test("async test", function(t){
  setTimeout(function(){
      t.ok(true, "i am async")
      t.end()
  }, 2000)
})

test("async test", function(t){
  setTimeout(function(){
      t.ok(true, "i am also async")
      t.end()
  }, 1000)
})

test("selftest after async", function(t){
  t.ok(true, "I pass")   
  t.ok(false, " I fail :( ")
  t.end()
})

non_async_testing_harness_tape_api.js

function test(msg, f){
 
  console.log(`Test: %c${msg}`, 'color: violet')
  f({ end, ok })

 
  /* Tape Api */
  function end(){} //noop
  function ok(expr, msg){
      expr
      ? console.log(`%c:)   pass: ${msg}`, 'color: darkgreen')
      : console.log(`%c:(   fail: ${msg}`, 'color: red')
  }
}


test("the truth", t => {
  t.ok(true, "I am true")
  t.ok(false, "I am false")
  t.end()
})

test("some math", t => {
  t.ok(Math.sqrt(16) === 4, "root of 16 is 4")
  t.ok(fetch instanceof Function, "fetch is cool")
  t.end()
})

ultra_nano_harness_nonasync.js

// I use this really simple one for throwaway testing or testing legacy js while in the devtools
const log = (...msg) => console.log(...msg)
const test = function t(expr, msg){ 
  expr ? log('%c!pass:'+msg, 'color:green') : log('%c?fail:'+msg, 'color:red') 
}

test(true,  'selftest pass')
test(false, 'selftest fail')