Test that a form field has an error with Cucumber and Capybara
You can use the step definition below to say this:
Then the "Last name" field should have an error
Capybara
Then /^the "([^\"]*)" field should( not)? have an error$/ do |field, negate|
expectation = negate ? :should_not : :should
page.send(expectation, have_css('.field_with_errors', :text => field))
end
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