jqwik: Domains inject parameterized values incorrectly

Testing Problem

The setup like this:

@Domain(MyDomain.class)
@Domain(DomainContext.Global.class)
class TestTest {
  @Property
  boolean test(@ForAll Predicate<Number> p1, @ForAll Predicate<Number> p2, @ForAll Number n) {
    return p1.or(p2).test(n) == (p1.test(n) || p2.test(n));
  }
}

class MyThing implements Predicate<CharSequence> {
  public boolean test(CharSequence cs) { return true; }
}

class MyDomain extends DomainContextBase {
  @Provide
  Arbitrary<MyThing> myThingArbitrary() {
    return Arbitraries.just(new MyThing());
  }
}

will produce:

  java.lang.ClassCastException:
    class java.lang.Long cannot be cast to class java.lang.CharSequence (java.lang.Long and java.lang.CharSequence are in module java.base of loader 'bootstrap')

but if you remove domain and provide MyThing right in test class - no problem.

About this issue

Original URL
State: closed
Created a year ago
Comments: 25 (7 by maintainers)

Most upvoted comments

pull request to solve most/all of the variance and assignment issues

Also available as 1.8.0-SNAPSHOT

jlink on Jul 16, 2023

Since a change to the behaviour of canBeAssignedTo(..) is relevant for a lot of hooks and domain implementations, I’ll move the current version to 1.8.0-SNAPSHOT.

jlink on Jul 10, 2023

Provided a fix and released it as “1.7.5-SNAPSHOT”.

@SimY4 Maybe you can try if your use case now works.

jlink on Jul 9, 2023

@SimY4 , please read “1.” in https://github.com/jqwik-team/jqwik/issues/499#issuecomment-1625947469

It seems you missed it

vlsi on Jul 8, 2023

Here’s a sample test case for TypeUsageTests

IMO (and the opinion of the compiler) the assertions are wrong:

assertThat(predicateDouble.canBeAssignedTo(predicateSuperNumber)).isTrue();
assertThat(predicateNumber.canBeAssignedTo(predicateSuperNumber)).isTrue();
assertThat(predicateNumber.canBeAssignedTo(predicateExtendsNumber)).isFalse();
assertThat(predicateDouble.canBeAssignedTo(predicateExtendsNumber)).isFalse();

should be

assertThat(predicateDouble.canBeAssignedTo(predicateSuperNumber)).isFalse();
assertThat(predicateNumber.canBeAssignedTo(predicateSuperNumber)).isTrue();
assertThat(predicateNumber.canBeAssignedTo(predicateExtendsNumber)).isTrue();
assertThat(predicateDouble.canBeAssignedTo(predicateExtendsNumber)).isTrue();

jlink on Jul 8, 2023