Rule Request: [HashValue overflow]

[kimdv]

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• Updated SwiftLint to the latest version
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Rule Request

I don't know 100% if this should be a rule, but it is possible in swift to overflow hash value by doing "test-1".hashValue + "test-2".hashValue

And for avoiding it it should be done like this "test-1".hashValue &+ "test-2".hashValue

It should be a optional rule.

It could prevent some crashes that people don't think about :)

[SDGGiesbrecht]

Maybe more in general, within computed properties named hashValue, prohibit all known checked operations (+, *, etc.) and recommend their unchecked variants (&+, &*, etc.)?

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It should be a optional rule.

I cannot think of any reasonable hashing situation where the checked variations would actually be better. Such a rule may as well be on by default.