Rounding negative FixedNumbers which are not using the default format results in an incompatible format error

[alexanderwende]

Hi, I think there's still a small bug in FixedNumber.round(), when working with negative numbers...

Describe the bug

Rounding negative FixedNumbers which are not in the default format results in an incompatible format error.

Reproduction steps

FixedNumber.from('-0.01101100205516751', 'fixed128x17').round(2)

Error produced

Uncaught Error: incompatible format; use fixedNumber.toFormat (argument="other", value={"format":{"signed":true,"width":128,"decimals":18,"name":"fixed128x18","_multiplier":"1000000000000000000"},"_hex":"0x0de0b6b3a7640000","_value":"1.0","_isFixedNumber":true}, code=INVALID_ARGUMENT, version=bignumber/5.4.0)
    at Logger.makeError (index.ts:213)
    at Logger.throwError (index.ts:225)
    at Logger.throwArgumentError (index.ts:229)
    at FixedNumber._checkFormat (fixednumber.ts:217)
    at FixedNumber.subUnsafe (fixednumber.ts:229)
    at FixedNumber.floor (fixednumber.ts:257)
    at FixedNumber.round (fixednumber.ts:294)

Environment

browser

Notes

When removing the minus sign from the number, no error is thrown.

Originally posted by @alexanderwende in #1629 (comment)

[ricmoo]

The bug is in the .floor() method which is an intermediate step of rounding.

It is fixed locally and will be going out in the next release.

Thanks! :)

[ricmoo]

This has been fixed in 5.4.2. Let me know if you still have any issues with it.

[alexanderwende]

@ricmoo Awesome, thanks a bunch! Will give it a shot soonish and will let you know.

[ricmoo]

Closing this now. If you find it is still an issue, please re-open.

Thanks! :)

[alexanderwende]

Hi, just go around to testing this out today. I haven't found any issues, had a test suite to run against, which was using a workaround for rounding negative numbers. After updating ethers to 5.4.2 and removing the workaround everything was green. So yeah, this one is good! :)

Thanks again for your quick help with this!