Bigint does not display correctly in Command Log, throws error on print to console of 0n

[dhorkin]

Current behavior

There are currently two issues with bigint in cypress.

1. when it prints log output, it says {} instead of serializing the bigint. If you click on the assertion, it displays properly in the console:
   
2. If either the expected or actual value is 0n, you get an exception when you click on it:
   

Desired behavior

• Bigints assertions should display their values in the command log (possibly with truncation)
• if you click on a bigint assertion that has 0n on expected or actual, no exception should occur

Test code to reproduce

describe('Bigint example', () => {
    it('Displays wrong', () => {
        expect(2n).to.equal(2n);
    });

    it('Exception on inspect', () => {
        expect(1n).to.equal(0n);
    })

    it('Exception on inspect 2', () => {
        expect(0n).to.equal(1n);
    })
});

Versions

This is present in 5.6.0 through 7.3.0, though you get different behavior for the exception in 5.6.0 and 7.3.0. In older versions, it doesn't show the exception and stack trace, but expected/actual are missing:

[jennifer-shehane]

Our code tries to run lodash _.trim() on the value, so _.trim(0n) throws that Cannot mix BigInt error. Code is here: https://github.com/cypress-io/cypress/blob/develop/packages/runner/src/lib/logger.js#L32:L32

I'm not sure exactly why it displays as {} instead of the bigint.

We would accept a pull request to fix the display and error.

[sainthkh]

expect {} to be {} is happening because of chai bug. It's fixed recently in 4.3.4.

[cypress-bot]

The code for this is done in cypress-io/cypress#16640, but has yet to be released.
We'll update this issue and reference the changelog when it's released.