Text Variants

<div>Logged in user</div>
<div id="user"></div>

setTimeout(() => {
  const el = document.getElementById('user')
  if (Math.random() < 0.5) {
    el.innerText = 'Joe Smith'
  } else {
    el.innerText = '@joe123'
  }
}, 500)

The username element might show the full user name or an alias. How do we confirm the possible text variants?

cy.contains('#user', '???')

We could use cy.contains with a regular expression

cy.contains('#user', /^(Joe Smith|@joe123)$/)

There are two downsides to the above approach.

1. Writing a dynamic regular expression with the value coming from a variable is complicated
2. cy.contains would not give you a good error if the element with id user is present, but its text does not match the given regular expression. It simply would say "0 elements found"

We could solve the second error by combining cy.get and cy.invoke queries

const username = '@joe123'
cy.get('#user')
  .invoke('text')
  .should('match', new RegExp(`^(Joe Smith|${username})$`))

Even better would be to use oneOf assertion

cy.get('#user')
  .invoke('text')
  .should('be.oneOf', ['Joe Smith', username])