refactor: store excluded references in a set which wraps IdentityHashMap

[algomaster99]

Reference #602

I thought I would refactor the code first as suggested by @slarse.

Just glancing at that code I would begin with wrapping that map in a set (with Collections.newSetFromMap), because the values aren't used :)

[algomaster99]

I am not sure what went wrong here, because tests passed on my machine. @khaes-kth could you please re-run the workflow? I think the failure could be because of the flaky tests.

[slarse]

@algomaster99 The scheduled builds on master have been failing for a few days, it's probably not related to this PR.

[khaes-kth]

@khaes-kth could you please re-run the workflow? I think the failure could be because of the flaky tests.

I did it, but it seems the problem isn't fix with a rerun.

@fermadeiral @monperrus : can you add @algomaster99 as a collaborator so that he can see the logs? It seems I do not have access to do it.

[monperrus]

Aman and you now have role "maintainer".

[algomaster99]

I did it, but it seems the problem isn't fix with a rerun.

The scheduled builds are failing as pointed out by Simon. I have created a PR to fix it, but it seems like that isn't the best way.

[algomaster99]

The tests should pass here after #617 is merged.

[algomaster99]

@khaes-kth once all tests are green, you may proceed to merge. This PR just refactors the code and it doesn't fix anything.

[algomaster99]

@khaes-kth ping for merge.

[khaes-kth]

LGTM!