Custom RSpec Meta Tag Validator

I’ve written my share of RSpec tests that look for specific meta tags in a web page under Capybara. It would be nice to be able to spell the following.

visit '/'
page.should have_meta({
                        'keywords' => 'spline, reticulating',
                        'description' => 'Splines are being reticulated here.'
                      })

Easy. This is my spec/support/matchers/have_meta.rb.

class HaveMeta
  attr_accessor :expected_val, :actual_val, :attribute

  def initialize(expected)
    @expected = expected
  end

  def matches?(page)
    @expected.all? do |key, val|
      meta = page.find(:xpath, "//head/meta[@property='#{key}' or @name='#{key}']")
      self.actual_val = meta&.native&.attribute('content')
      self.expected_val = val
      self.attribute = key
      actual_val.include? expected_val
    end
  end

  def failure_message_for_should
    "expected '#{attribute}' to contain '#{expected_val}' in '#{actual_val}'"
  end
end

def have_meta(expected) # rubocop:disable Naming/PredicatePrefix -- RSpec matcher factory.
  HaveMeta.new(expected)
end

This is a lot better than having to compare strings or making manual XPath queries.

Daniel Doubrovkine

Custom RSpec Meta Tag Validator rspec | capybara | ruby | testing

Custom RSpec Meta Tag Validator