[useId] Trade random collisions for collisions on overflow #29781
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eps1lon
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Previously ids were picked at random from 1-1.000.000.000 (1e9). Naively one could assume that the probability of a collision if two numbers are drawn is 1e9 * 1e9. However, the birthday problem puts the probability at ~1e9 (see "Probability of a shared birthday").
The problem is that we fairly quickly reach a point were collisions are pretty likely e.g. with 200 random ids on a page (conceivable with inputs and tooltips on normal pages or even more problematic in our documentation) we have a 1:50.000 collision chance. https://instacalc.com/28845 for experimentation.
Instead, we can just increment and delay collisions to the point of integer overflow (at which point we almost certainly had a collision anyway)