Is there syntax for adding a clue to ScalaTest matchers?

Question

Is there an idiom for adding a clue to a ScalaTest matcher such that the clue will become part of the assertion failure? I know that I can currently write a ScalaTest assertion like this:

withClue("expecting a header row and 3 rows of data") {
  rowCount should equal(4)
}

Is this the only syntax for adding the clue to the assertion? It would be nice to be able write an assertion to look something like this:

rowCount should equal(4) because("expecting a header row and 3 rows of data")

score 18 · Accepted Answer · answered Feb 03 '15 at 21:25

18

If you mixin AppendedClues you can write the withClue as a suffix:

class TestSuite extends FlatSpec with Matchers with AppendedClues {
  3 should equal(4) withClue("expecting a header row and 3 rows of data")
}

Also works without parens of course.

answered Feb 03 '15 at 21:25

gzm0

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3

Nice. Some mention of this should be added to the "Using Matchers" section of the ScalaTest User Guide. – Daryl Odnert Feb 03 '15 at 21:50

Is there syntax for adding a clue to ScalaTest matchers?

1 Answers1