Remove the tedium of formulaic form filling with Capybara.
Formulaic allows you to specify a hash of attributes to be input rather than procedurally calling Capybara’s DSL methods.
gem 'formulaic', group: :testfeature 'New user registration' do scenario 'successfull sign up' do visit sign_in_path fill_form(:user, { name: 'Caleb', email: 'caleb@thoughtbot.com', 'Terms of Service' => true }) click_on submit(:user) expect(page).to have_content t('user.create.success') end endfill_form(model_name, :new, attributes)fill_form provides an interface to completely filling out a form. Provide the model_name as a symbol and attributes as a hash of column name => database value or label string => database value.
If an attributes key is a String, it will be used as the literal label. For Symbol we will attempt to translate, fall back to human_attribute_name if available, then call to_s.
input(model_name, field)input gives an easy way to find the translated text of an input. It is primarily used internally to fill <input>s, but is provided in the public API as it could be useful.
submit(model_name, :create)submit functions like input, but finds the translation for the submit button of the form. model_name should be the same as what you provide to fill_form. Typically, the return value of submit will be passed directly to Capybara’s click_on method.
If you are submitting a form that is not for the create action, you may need to pass the action:
submit(:user, :update)The model_name and action should match up to the helpers.submit.<model_name>.<action> translations.
fill_form_and_submit(:user, :new, attributes)Effectively a fill_form followed by click_on submit, but smart enough to fill_form with :new and submit with :create and the edit/update cousin.
If you have nested forms, through fields_for (or any variant), you are able to fill them with an extra call to fill_form.
fill_form(main_model_name, main_model_attributes) fill_form(nested_model_name, nested_model_attributes)# spec/spec_helper.rb RSpec.configure do |config| config.include Formulaic::Dsl, type: :feature end# test/test_helper.rb class ActionDispatch::IntegrationTest include Capybara::DSL include Formulaic::Dsl endIntegration with Factory Bot
fill_form(:user, attributes_for(:user))You may have attributes included in your User factory that don’t pertain to sign up:
fill_form(:user, attributes_for(:user).slice(*sign_up_attributes)) # ... def sign_up_attributes [:name, :email, :terms_of_service] endIntegration with Capybara::TestHelper
class BaseTestHelper < Capybara::TestHelper include Formulaic::Dsl endor alternatively delegate the needed methods:
class FormTestHelper < BaseTestHelper delegate_to_test_context(:fill_form, :input, :submit, :fill_form_and_submit) endFormulaic relies pretty heavily on the assumption that your application is using translations for SimpleForm and input helpers, using the simple_form.labels.<model>.<attribute> and helpers.submit.<model>.<action> conventions.
You can still use Formulaic by using strings as keys instead of symbols, which it knows to pass directly to fill_in rather than trying to find a translation. You’ll need to find submit buttons yourself since submit is a thin wrapper around I18n.t.
Formulaic assumes your forms don't use AJAX, setting the wait time to 0. This can be configured using:
Formulaic.default_wait_time = 5-
Formulaic currently supports the following mappings from the
#classof the attribute values to Capybara method calls:Classes Formulaic’s action Stringfill_in,choose, orselectDate,ActiveSupport::TimeWithZoneselectyear, month, and dayTrueClasscheckFalseClassuncheckArraycheckorselecteach array member, which should all be strings. If not all items can be selected or checked, an error will be thrown.Fileattach_filewithFile#path -
Formulaic is currently tied to
simple_formtranslations and field structure. If you pass a string for the attribute, we’ll try to fill the input that relates to that label. We would be happy to work with you to add support for other form builders. -
Formulaic currently does not support forms with duplicate labels, as it is designed to be as similar as possible to a user completing a form—it looks at the labels to determine where to fill what data.
-
Formulaic can’t figure out how to fill fields with HTML labels:
page.fill_in('<strong>Text</strong> here', with: 'something')doesn’t work with Capybara. The usual workaround is to pass a CSS selector (which you can do by passing a string as the attribute key). -
Formulaic can't handle multiple file attachments on the same input.
Formulaic is maintained by Caleb Hearth and formerly thoughtbot with the help of community contributors. Thank you!

