System test to test correct react display

posts_test.rb

require "application_system_test_case"

class OrdersTest < ApplicationSystemTestCase
  test "cancel post" do
    setup_remote
    visit post_index_url
    
    first('.entry').click_on 'Add Post'
    
    fill_in 'Post_name', with: 'My Post'
    fill_in 'Post_content', with: 'A great post!'

    assert_no_selector "meme"

    select 'Fun', from: 'category'

    assert_selector "meme"
  end
end