To get or set configuration options, use Cypress.config().
var myConfig = Cypress.config()
expect(myConfig).to.have.property('animationDistanceThreshold', 5)
expect(myConfig).to.have.property('baseUrl', null)
expect(myConfig).to.have.property('commandTimeout', 4000)
expect(myConfig).to.have.property('requestTimeout', 5000)
expect(myConfig).to.have.property('responseTimeout', 20000)
expect(myConfig).to.have.property('viewportHeight', 660)
expect(myConfig).to.have.property('viewportWidth', 1000)
expect(myConfig).to.have.property('visitTimeout', 30000)
expect(myConfig).to.have.property('waitForAnimations', true)
expect(Cypress.config('visitTimeout')).to.eq(30000)
Cypress.config('visitTimeout', 20000)
expect(Cypress.config('visitTimeout')).to.eq(20000)