Add Bijectors integration tests

[mhauru]

Copied over from EnzymeAD/Enzyme.jl#2037.

Closes #348

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

see 1 file with indirect coverage changes

[willtebbutt]

This is great, thank you for opening this.

Regarding the failing test: it's one that we know about already, and is related to this rather annoying upstream problem. We need some way of indicating that this is a problem. I propose the following:

1. exclude the offending example from the main test suite
2. call build_rule on the test case, which should be enough to trigger the error. Put this call inside a @test_broken thing, so that when we eventually fix the problem we find out about it.

Does this sound sensible to you?

[mhauru]

I put in the following, does this do what you wanted?

        TestCase(
            function (x)
                layer = Bijectors.PlanarLayer(x[1:2], x[3:4], x[5:5])
                flow = Bijectors.transformed(
                    Bijectors.MvNormal(zeros(2), LinearAlgebra.I),
                    layer,
                )
                x = x[6:7]
                return Bijectors.logpdf(flow.dist, x) -
                       Bijectors.logabsdetjac(flow.transform, x)
            end,
            randn(Xoshiro(23), 7);
            name = "PlanarLayer7",
            # TODO(mhauru) Broken on v1.11 due to
            # https://github.com/compintell/Mooncake.jl/issues/319
            broken=(VERSION >= v"1.11"),
        ),

        if case.broken
            @test_broken begin
                test_rule(Xoshiro(123456), case.func, case.arg; is_primitive=false)
                true
            end
        else
            test_rule(Xoshiro(123456), case.func, case.arg; is_primitive=false)
        end

[willtebbutt]

This is perfect. Thank you!

[willtebbutt]

I'll merge when CI has passed.