Whether the post or page has a tag, as the settings panel shows it.
Examples
Then the post should have the tag "News"
Then the post should have the tag "Guides"
Then the post should not have the tag "Travel"
And the page should not have the tag "News"
Then the post should have the tag "A tag from the suite"
Pattern
Then(/^the (?:post|page) should( not)? have the tag "([^"]*)"$/, …)
Part of @webship-js/ghost-steps (github.com/webship/ghost-steps), a step pack for Webship-js 2.0.x.