Don't use PHP's fmod #470
Don't use PHP's fmod #470
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PHP's fmod has some quirks. The private fmod function wraps it to iron out some of those quirks but ultimately it's better to just not use it.
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Good catch - PHP's fmod() loses an unacceptable level of precision.
However.... this whole method is a mess, and most of it is unnecessary. Realistically, all we need to know is whether the remainder is sufficiently close to zero. Which is essentially the following:
$threshold = 0.0000000001;
return abs($value - round($value / $factor) * $factor) < $threshold;Seeing as that's almost a one-liner, and this method is only called in two places (divisibleBy and multipleOf, which are equivalent anyway), my feeling is that this should be inlined. Seeing as you're fixing the fmod problem anyway, might as well go the whole way and throw out all the other useless junk.
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Well I didn't want to criticise the existing code, but yes that function is a bit of a mess. That's mostly because it's trying to work around the issues with PHP's fmod but if we're not using that any more we can simplify the function. I think it's still too complicated for a one liner and if it's used in two places it's better to keep the code in one place. |
Now that the private fmod function is not using PHP's fmod we can remove the code which was working around it's quirks.
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Per #469 I think it would be nice to have a test demonstrating the false negative. |
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@erayd should I hold out for a test on this one? |
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@bighappyface I'm happy with it as-is. It would be handy to have a test at some point, but I don't think we should be delaying this fix for it, noting the lack of resources. |
This fixes #469.