Scalatest: how to check if a collection contains element that satisfies certain criteria

Question

Say I have a list of books:

val books = List(
    Book(title="Foo", year=2014),
    Book(title="Bar", year=2014))

How to check with a single expression if collection books is not empty and only contains books published in 2014?

Answer 1

Using matchers:

books should not be empty
books.map(_.year) should contain only (2014)

Or just:

books.map(_.year) should contain only (2014)

since this check asserts that the list is not empty.