The Worst Bug Ever–Randomly Losing Your Best Players

medium.com

11 points·a-bit-of-code··5 comments

The title of this discusses losing "best players", so I was expecting the bug to be related to player performance in some way -- having won too many games, or scored too many points, or collected too much loot, etc. The bug as described doesn't appear to be related to gameplay at all, so I'm not sure what the title was referring to. Unfortunately, the actual bug appears to just be some Unity code incorrectly parsing data related to in-app purchases.

It's "best players" from the vendor's perspective: players found willing to pay money out of pocket.

FTA: “Well, Apple defines that, but I guess that’s kind of a pain to figure out and it’s just easier to try to decode and see what happens! YOLO!”

From what I understand (also FTA: “The Unity IAP team found themselves having to harden their code against random data”) the fix wasn’t to read the documentation and do the right thing, but to go deeper in on “if we step carefully through this minefield, we probably will survive”.

And Unity’s customer is happy with that!

> [...] harden their code against random data [...]. It’s a hard problem to correctly parse complex structures that are incorrectly formatted. This is what led to unhandled exceptions and infinite loops.

I was expecting something much more interesting from the title, or mere posting of the story. It seems it was picked because of the cost/impact of the bug rather than the technical surprise/complexity.

Seems like an odd bug to slip through testing, especially for a 4.1x release. Considering that validating string inputs, etc., is pretty much textbook. Unless Unity doesn’t bother to do testing, which also seems unlikely for their flagship multi million, or billion(?), dollar product.

Reply on news.ycombinator.com