All Challengesintermediate

Promise chaining order

Understanding the order of operations in Promise chains is critical for debugging AI code.

promiseschainingasyncerror handling
javascript
function processOrder(orderId) {
  return fetch(`/api/orders/${orderId}`)
    .then(res => res.json())
    .then(order => {
      if (order.status === 'pending') {
        return fetch(`/api/orders/${orderId}/confirm`, { method: 'POST' })
      }
      return order
    })
    .then(result => {
      if (result instanceof Response) {
        return result.json()
      }
      return result
    })
    .catch(err => {
      console.error('Order failed:', err)
      return null
    })
}

Question

If the order status is "shipped", what does the second .then receive as its argument?

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