sketch.js

test.register(function hoge () {

})

register = function (name, fn) {
  function add (name, fn) {
    Test.prototype[name] = function () {
      this._assert()
      return fn()
    }
  }

  add(name, fn)
  Object.keys(fn).forEach((key) => add(key, fn))
}

test((t) => {
  t.hoge() // t.assertCount++
})