Web3JS – How to Remove Trailing Zero from web3.toAscii() Conversion

The equivalent should be web3.utils.hexToAscii

web3.utils.hexToAscii('0x4920686176652031303021');
> "I have 100!"

To elaborate on the previous answer - from the official documentation of BN:

Note: decimals are not supported in this library.

Here, the term decimals refers to numeric values with digits after the decimal point (i.e., non-integers).

When creating a BN object, you can pass either an integer or a string which represents an integer.

And looking at your tests, it seems that you can simply use the String result of web3.utils.fromWei rather than converting it to a BN instance and then back to a String.

If for any reason you need a non-integer big-number, then you can use either bignumber.js or decimal.js.

Just bare in mind that for interacting with your contract via web3 v1.x, you'll still need to use BN instances.

In addition to all of the above (and this too should be credited to the previous answer):

Back in the days of web3 v0.x which has relied on BigNumber, if the user passed a non-integer, then web3 would just truncate it and pass the integer value of it to the contract. Subsequently, the contract's behavior could be different than expected, and not necessarily at that exact point during execution, but possibly later. In order to protect the user from this type of scenario (which can be rather difficult to identify "on the spot"), web3 v1.x has changed this dependency and introduced the usage of BN instead of BigNumber.