Assert the editor shows a notice (a snackbar) such as "Post published.", "Post updated." or "Draft saved."
Examples
Then I should see the editor notice "Post published."
And we should see the editor notice "Post updated."
Then I should see the editor notice "Page published."
And I should not see the editor notice "Post updated."
Then we should see the editor notice "Draft saved."
Pattern
Then(/^(I |we )*should( not)* see the editor notice "([^"]*)"$/, …)
Part of @webship-js/wordpress-steps (github.com/webship/wordpress-steps), a step pack for Webship-js 2.0.x.