There seems to be no built-in matcher in RSpec to check if a string contains terms in the desired order. A simple workaround is to use a regular expression that also matches newlines (m-modifier).

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Cons:

• The readability when terms need to be escaped is bad
• A failed spec has an error which needs manually action to be understood (Search if terms appear and in which order)

Example:

expect(ActionMailer::Base.last.to_s).to match(/Dear customer.*Account canceled.*You Awesome Company/m)