The “standard” way of using matchers is
value must matcher. However there are several allowed variations:
// use 'should' instead of 'must' 1 should beEqualTo(1) // use 'beXXX' and 'haveXXX' as 'be XXX' and 'have XXX' 1 must be equalTo(1) List(1) must have size(1) // use 'not' to negate a matcher List(1) must not have size (1)
Finally there are some shortcuts for the equality matcher:
1 must_== 1 1 mustEqual 1 1 === 1 // with a negation 1 must_!= 2 1 mustNotEqual 1 1 !=== 1
Seq() must be empty is being parsed as
(Seq() must be) empty where
empty is a “Postfix operator”. By default Scala disallows postfix operators but they are enabled in specs2 specifications thanks to the
org.spec2.control.LanguageFeatures trait providing the
language.postfixOps implicit definition.
If that implicit definition conflicts with your own import of
language.postfixOps you can use the
org.spec2.control.NoLanguageFeatures trait to deactivate it.