I am testing at the moment some smart contracts with truffle(mocha/chai/chai-as-promised) and have the following problem:

I have a getter, and this getter delivers an UINT value, then when I try to test the value with the instance.getMemberCount().should.eventually.equal(4) the result is: expected { Object (s, e, ...) } to equal 4.

Interesting fact is that when I try to compare the values directly with ‘==’ there is no problem.. (for example: assert.equal(instance.getMemberCount() == 4))

Has Mocha/Chai problems transforming the uint values?

  • getMemberCount().toNumber() ? maybe Aug 11 '17 at 3:55
  • @ВиталийШвецов - there is no toNumber() in JavaScript or I am wrong? I have tried with Number(), parseInt() - but the result is NaN, because we have 'object Promise' and I am still stuck ..
    – val3ri
    Aug 11 '17 at 7:23
  • 1
    @val3ri Web3 has a BigNumber object which has a toNumber. ethereumbuilders.gitbooks.io/guide/content/en/… see "web3.toBigNumber"
    – ABCD.ca
    Jun 30 '18 at 21:30

You can use .valueOf() to get the return value from the getter function.

I've used this in one of the test cases I wrote sometime back.

You can take a look at this for reference.

Hope this helps.

  • Thanks for the github repository link I will search for answers there! With .valueOf() the result is: [object Promise]. And after printing the result is: { [String: '4'] s: 1, e: 0, c: [ 4 ] }. JavaScript is converting somehow this object and the comparison with "==" works.
    – val3ri
    Aug 14 '17 at 10:08

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