Helper specs

Helper specs are marked by type: :helper or if you have set config.infer_spec_type_from_file_location! by placing them in spec/helpers.

Helper specs expose a helper object, which includes the helper module being specified, the ApplicationHelper module (if there is one) and all of the helpers built into Rails. It does not include the other helper modules in your app.

To access the helper methods you're specifying, simply call them directly on the helper object.

NOTE: helper methods defined in controllers are not included.

A helper method that returns a value

Given a file named "spec/helpers/application_helper_spec.rb" with:

require "rails_helper"

RSpec.describe ApplicationHelper, type: :helper do
  describe "#page_title" do
    it "returns the default title" do
      expect(helper.page_title).to eq("RSpec is your friend")
    end
  end
end

And a file named "app/helpers/application_helper.rb" with:

module ApplicationHelper
  def page_title
    "RSpec is your friend"
  end
end

When I run rspec spec/helpers/application_helper_spec.rb

Then the examples should all pass.

A helper method that accesses an instance variable

Given a file named "spec/helpers/application_helper_spec.rb" with:

require "rails_helper"

RSpec.describe ApplicationHelper, type: :helper do
  describe "#page_title" do
    it "returns the instance variable" do
      assign(:title, "My Title")
      expect(helper.page_title).to eql("My Title")
    end
  end
end

And a file named "app/helpers/application_helper.rb" with:

module ApplicationHelper
  def page_title
    @title || nil
  end
end

When I run rspec spec/helpers/application_helper_spec.rb

Then the examples should all pass.

Application helper is included in helper object

Given a file named "spec/helpers/widgets_helper_spec.rb" with:

require "rails_helper"

RSpec.describe WidgetsHelper, type: :helper do
  describe "#widget_title" do
    it "includes the app name" do
      assign(:title, "This Widget")
      expect(helper.widget_title).to eq("The App: This Widget")
    end
  end
end

And a file named "app/helpers/application_helper.rb" with:

module ApplicationHelper
  def app_name
    "The App"
  end
end

And a file named "app/helpers/widgets_helper.rb" with:

module WidgetsHelper
  def widget_title
    "#{app_name}: #{@title}"
  end
end

When I run rspec spec/helpers/widgets_helper_spec.rb

Then the examples should all pass.

Url helpers are defined

Given a file named "spec/helpers/widgets_helper_spec.rb" with:

require "rails_helper"

RSpec.describe WidgetsHelper, type: :helper do
  describe "#link_to_widget" do
    it "links to a widget using its name" do
      widget = Widget.create!(:name => "This Widget")
      expect(helper.link_to_widget(widget)).to include("This Widget")
      expect(helper.link_to_widget(widget)).to include(widget_path(widget))
    end
  end
end

And a file named "app/helpers/widgets_helper.rb" with:

module WidgetsHelper
  def link_to_widget(widget)
    link_to(widget.name, widget_path(widget))
  end
end

When I run rspec spec/helpers/widgets_helper_spec.rb

Then the examples should all pass.