public function testIsNaryPredicate() { $predicate = Callables::newPredicate(function ($a, $b, $c) { return false; }); $this->assertFalse(Callables::isUnaryPredicate($predicate)); $this->assertFalse(Callables::isBinaryPredicate($predicate)); $this->assertTrue(Callables::isNaryPredicate($predicate)); }