Core htmx client side validation tests

• hyperscript validation error prevents request16ms ‣

  this.server.respondWith('POST', '/test', 'Clicked!')
  var form = make('<form hx-post="/test" hx-trigger="click">' +
          'No Request' +
          '<input _="on htmx:validation:validate if my.value != \'foo\' call me.setCustomValidity(\'Nope\') ' +
          '                                      else call me.setCustomValidity(\'\')" id="i1" name="i1">' +
          '</form>')
  htmx.trigger(form, 'htmx:load')
  byId('i1').value = 'boo'
  form.textContent.should.equal('No Request')
  form.click()
  this.server.respond()
  form.textContent.should.equal('No Request')
  byId('i1').value = 'foo'
  form.click()
  this.server.respond()
  form.textContent.should.equal('Clicked!')