Numbers past 53 bits break toCurrency and toNumber

[JackieCalapristi]

See here:

Upon further investigation, this is actually a problem with javascript's toFixed() function used by i18n-js here:

i18n-js/app/assets/javascripts/i18n.js

Line 48 in 6431b92

return decimalAdjust('round', number, -precision).toFixed(precision);

And the reason toFixed() breaks on numbers like this is because JS only supports 53 bit integers which 300000000000020000 is larger than. See more info on this here: http://2ality.com/2012/07/large-integers.html.

Ideally we would want to find a patch for this that doesn't break rounding for imprecise floating points (which appears to be the reason toFixed() was added to this line here:

i18n-js/app/assets/javascripts/i18n.js

Line 48 in 6431b92

return decimalAdjust('round', number, -precision).toFixed(precision);

).

Not as ideally we could add a disclaimer for this known issue instead or in the meantime. I'm happy to help in any way I can on this!

[PikachuEXE]

Do you any known patch that solves this issue?
I have never encountered any large enough number yet

[PikachuEXE]

Added to known issues until there is a permanent fix available
608d552

[JackieCalapristi]

This is a widely recognized issue with Javascript. Javascript is very self-aware about this as well.

This issue can be solved with a library called BigInteger.

Before implementing a patch we could also:

• Warn when user input goes past Number.MAX_SAFE_INTEGER for all functions affected by this.
• Write a disclaimer in an appropriate readme for all functions affected by this. We could even reference TC39 proposals in the works to address this.

[PikachuEXE]

I wonder how the "warning" be sent
Since this library might be used in browser / NodeJS process / even mobile app (screenshot in #513)