module ActionView::TestCase::Behavior

Returns the content rendered by the last render call.

The returned object behaves like a string but also exposes a number of methods that allows you to parse the content string in formats registered using .register_parser.

By default includes the following parsers:

.html

Parse the rendered content String into HTML. By default, this means a Nokogiri::XML::Node.

test "renders HTML" do
  article = Article.create!(title: "Hello, world")

  render partial: "articles/article", locals: { article: article }

  assert_pattern { rendered.html.at("main h1") => { content: "Hello, world" } }
end

To parse the rendered content into a Capybara::Simple::Node, re-register an :html parser with a call to Capybara.string:

register_parser :html, -> rendered { Capybara.string(rendered) }

test "renders HTML" do
  article = Article.create!(title: "Hello, world")

  render partial: article

  rendered.html.assert_css "h1", text: "Hello, world"
end

.json

Parse the rendered content String into JSON. By default, this means a ActiveSupport::HashWithIndifferentAccess.

test "renders JSON" do
  article = Article.create!(title: "Hello, world")

  render formats: :json, partial: "articles/article", locals: { article: article }

  assert_pattern { rendered.json => { title: "Hello, world" } }
end