Error: utils.isBN returns wrong boolean with an fake object

[skqksh]

Describe the bug

caver.utils.isBN returns 'true' but it should have to return 'false'

 const notBn = {}
notBn.constructor = {}
notBn.constructor.name = 'BN'
console.log(caver.utils.isBN(test))

How to reproduce
same with above

Expected behavior
caver.utils.isBN should work as like as BN.js works

Attachments
web3.js already covered that

Environment (please complete the following information)

• caver-js ver 1.3.1

Additional context
NA

[jimni1222]

Hi :)

Is this issue related with web3/web3.js#1777?
I will apply this modification to caver-js.
And also i will add test case what you describe above.

Thank you for reporting this issue !

[jimni1222]

@skqksh
Hi, PR is uploaded :)
#207

If there is any opinion about this change, please feel free to comments on PR.