Catty-237: Convert UserVariable from Objective-C to Swift

[neel-makhecha]

Converted UserVariable class from Objective-C to Swift with various other changes.

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[m-herold]

Please fix tests.

[m-herold]

Do not merge this PR yet. As mentioned in the Jira ticket, this PR is blocked by CATTY-236.

[m-herold]

Any news on that pull request?

[neel-makhecha]

Any news on that pull request?

I have been working on this. There was a first runtime issue where null pointer from objective-C function call was being passed to a non-optional argument of isEqual method, which is fixed by making it optional.
But there is still another runtime exception that I am receiving in XMLAbstractTest and trying to track that down. The 'project' instance is getting nil, which is force unwrapped. I am attaching a screenshot for the same too... it would be very helpful if you can point some right directions to look for.
Thank you

[m-herold]

If you push your most recent changes for the isEqual method I will have a look at it.

[neel-makhecha]

If you push your most recent changes for the isEqual method I will have a look at it.

Done!

[m-herold]

Your issue occurs because of some Objective C reflection we use in the deprecated Parser for old Catrobat language versions. Simply adding @objc(UserVariable) to your newly created Swift class should resolve the problem.

[neel-makhecha]

Your issue occurs because of some Objective C reflection we use in the deprecated Parser for old Catrobat language versions. Simply adding @objc(UserVariable) to your newly created Swift class should resolve the problem.

Thanks! It's now fixed. Please review.

[m-herold]

This pull request is not compiling. Please revise.

[neel-makhecha]

This pull request is not compiling. Please revise.

Hi Michael, everything seems okay now, I just had to rebase and update a few method calls as per a slightly new signature of isEqual. Please review.

[neel-makhecha]

Hi Michael, Please review the latest commit.

[m-herold]

Thanks! Really great to see that the code base's quality is gradually increasing. I have attached a few suggestions.

[neel-makhecha]

Hi Michael, please review the latest commits.

[m-herold]

Thank you! Please make those few final changes and squash your commits.

[neel-makhecha]

Done!