fix: Rare arithmetic overflow crash in MPIHasher #246
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mparticle-automation
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Summary
There is an extremely rare case where a specific string could cause an overflow error when calling
MPIHasher.hashString()due to not using the overflow addition operator. I've changed the code from a regular addition to overflow addition which matches the original Objective-C logic and was the intended behavior.Testing Plan
Due to the nature of this hash function I was unable to write a unit test to reproduce the bug, but I reproduced it manually by setting
var hash: Int32 = Int32.maxto confirm that it was hypothetically possible and that switching to the overflow addition operator fixes the issue.Reference Issue (For mParticle employees only. Ignore if you are an outside contributor)