Mutating "return true" with return true, imposible to kill the mutation

[martinchaves]

Hi, we are having problems with the BooleanTrueReturnValsMutator.
We have a code like:

data.stream()
        .map(
            x -> {
              try {
                operation.accept(x);
                return true; // Mutated with BooleanTrueReturnValsMutator and BooleanFalseReturnValsMutator
              } catch (RuntimeException e) {
                return false; // Mutated only with BooleanTrueReturnValsMutator
              }
            })
        .reduce(true, Boolean::logicalAnd);

Because the method return true is mutated with a return true the mutation survives all test.
We only experienced this problem with lambdas with try/catch

Tested with gradle plugin 1.7.0, pitest 1.70 and 1.7.4, junit 5.8.2 with 0.15 junit plugin using JDK 8, 11 and 17.

I couldn't figure out if there are something wrong in our setup.
See the POC project.

[hcoles]

Thanks @kiov, I'll take a proper look in a moment, but at a first glance this looks like a bug. Equivalent mutants like this should be filtered out. I'm guessing the try catch block is tripping up pitest's analysis.

The POC project will be a big help - thanks for that.

[hcoles]

That was indeed a bug. The analysis didn't handle the additional label nodes added when an boxed boolean was returned from a try block.

Fix is merged, will be in the next release.

Thanks again.

[martinchaves]

That was fast!!

My OCD with 100% coverage will be pleased 😁

Thanks you!