Groovy custom truth and equals()

ProblemWithGroovyTruth.groovy

class Predicate {
    boolean value
    boolean asBoolean() { value }
}

// Works: 
assert new Predicate(value: true)
assert !new Predicate(value: false)
assert (new Predicate(value: true) as Boolean == true)
assert (new Predicate(value: false) as Boolean == false)

// Does not work:
assert (new Predicate(value: true) == true)
assert (new Predicate(value: false) == false)

//Output:
//Assertion failed: 
//
//assert (new Predicate(value: true) == true)
//        |                          |
//        Predicate@3ee3f8b9         false
//
//    at ConsoleScript29.run(ConsoleScript29:13)

the following call coerces to a boolean value:

assert new Predicate(value: true)

== causes the equals method to jump in, no boolean coercion here

Thanks for the explanation, that makes sense.