Rounding 5 with negative numbers

[Railslide]

When rounding negative numbers, 5 behaves differently from what I would expect / how it works in other programming languages.

roundTo(0.375, 2);
// 0.38

roundTo(-0.375, 2);
// -0.37 (I was expecting -0.38)

Not sure if that's by design or not.

[sindresorhus]

Yeah, that seems like a bug.

[SamVerschueren]

What is the expected result of the following expressions?

roundTo.up(-0.375, 2);
roundTo.down(-0.375, 2);

Does up means more negative and thus -0.38 and down more positive and thus -0.37 or the other way around?

[Railslide]

I would expect

roundTo.up(-0.375, 2);
// -0.37
roundTo.down(-0.375, 2);
// -0.38

Actually, it looks like Math.round is the culprit, since:

Math.round(-0.5);
// 0
Math.round(0.5):
// 1

[sindresorhus]

Fixed by #8.