Mocha assertions not returning correctly on assert.equal with BN

Question

Is this an issue with deep matching/object identity?

AssertionError: expected <BN: 204fce5e3e25026110000000> to equal <BN: 204fce5e3e25026110000000>

It seems strange that chai.should seems to work fine with the same vars:

// works
supplyCap.should.be.bignumber.equal(_cap);

// doesn't work
assert.equal(supplyCap, _cap);

Answer 1

Change this:

assert.equal(supplyCap, _cap);

To this:

assert.equal(supplyCap.toString(), _cap.toString());

Answer 2

Consider using bn-chai if you do it a lot.

Then you can do:

expect(new BN('1')).to.eq.BN(new BN('1'));
expect(new BN('1')).to.eq.BN('1');
expect(new BN('1')).to.eq.BN(1);

Answer 3

I'm not sure if this solution applies to your case, but whenever I handle numbers from smart contracts I use the Number(...) constructor as follows.

assert.equal(Number(supplyCap), Number(_cap));

And works perfectly for me.