getBytes abbreviations exceed Long storage but no Exception is thrown

[mslinn]

Given the following in a configuration file (2 yottabytes):

bytes2=2Y

Attempting to read using getBytes returns zero and no exception is thrown:

myConfig.getBytes("bytes2")

I don't think it makes sense to support any abbreviations that result in Long overflow, yet the source code shows support for K (kilo), M (mega), G (giga), T(tera), P (peta), E (exa), Z (zetta) and Y (yotta). Most of these silently fail instead of throwing an exception like

new ArithmeticException("Long overflow");

[havocp]

heh - I guess I just copied a list of units prefixes from somewhere and didn't think about it much. agreed it should throw.

[mslinn]

Might be good to document all of the supported conversions: K (kilo), M (mega), G (giga), T(tera), P (peta), E (exa), Z (zetta) and Y (yotta). I saw Kibi..Yobi in the code, not sure how they would be notated in a config file so that might also be a good thing to document.

How about providing a version that supports arbitrarily large numbers by returning BigInteger instead of Long? Might call it getBytesAsBigInteger. I think the practical upper limit for BigInteger is something like (2^31)-1 digits (maximum length of a String), so no problem to store a YottaByte in BigInteger.

[havocp]

The sizes are documented here: https://github.com/typesafehub/config/blob/master/HOCON.md#size-in-bytes-format

I agree it would be nice to have a BigInteger version. I added #172 for that to keep it separate from fixing the bug in the existing getBytes.