How to assert an element is present after a click in Hound? - selenium

Question

I'm using Hound as webdriver framework for leveraging Selenium in Elixir. I'm testing facebook account creation. After I fill out a negative test (firstname = Roberto, lastname = asdlkfj;)I click submit and I am trying to get an error for not having a correct last name. The problem is Hound isn't waiting for the element to be displayed and returns an element not found error. How can I handle this and have the test wait until the element is loaded? Here's my code:
test "Last name with random characters" do
counter = :rand.uniform(100)
navigate_to "https://www.facebook.com"
first_name = find_element(:name, "firstname")
fill_field(first_name, "Jorge")
last_name = find_element(:name, "lastname")
fill_field(last_name, "asdfja;lsdf")
email_input = "robbie#{counter}#gmail.com"
email = find_element(:name, "reg_email__")
fill_field(email, email_input)
confirm_email = find_element(:name, "reg_email_confirmation__")
fill_field(confirm_email, email_input)
password_input = "123456Test"
password = find_element(:name, "reg_passwd__")
fill_field(password, password_input)
#Birthday
birth_month = find_element(:css, "#month > option:nth-child(5)")
birth_day = find_element(:css, "#day > option:nth-child(25)")
birth_year = find_element(:css, "#year > option:nth-child(22)")
click(birth_month)
click(birth_day)
click(birth_year)
#gender
select_gender = find_element(:css, "#u_0_s > span:nth-child(2)")
click(select_gender)
sign_up_button = find_element(:name, "websubmit")
click(sign_up_button)
search = find_element(:id, "#reg_error_inner")
# found = element_displayed?("#reg_error_inner")
IO.puts(search)
# assert found == true
# :timer.sleep(10000)
end```

Answer 1

Use search_element instead of find_element. search_element will return {:ok, element} on success and {:error, error} on failure. If you just want to assert the element exists, then you can:
assert {:ok, _} = search_element(:id, "#reg_error_inner")
If you want to also have it in a variable for further processing, then:
assert {:ok, element} = search_element(:id, "#reg_error_inner")
If you want to convert it to a boolean, then:
match?({:ok, _}, search_element(:id, "#reg_error_inner"))