RSpec/rails & Capybara: #within


I’m new to Capybara and after a good amount of google, I still can’t
figure out how the #within methods works!
I can use it only if I call visit before? There’s no way to use it on a
string, like the page = Capybara.string(html_string) trick?

When describe a view, I want something like that:
describe “path/to/view.html.erb” do
it “should pass” do
within(‘form#id’) {
should have_selector ‘input’, type: ‘submit’
should have_selector ‘input’, type: ‘text’, value: ‘default’
# …

PS: Hope this is the right sections! ^^"