JSON stringify that safely handles circular references (found on StackOverflow somewhere)

safe-stringify.js

// safely handles circular references
JSON.safeStringify = (obj, indent = 2) => {
  let cache = []
  const retVal = JSON.stringify(
    obj,
    (key, value) =>
      typeof value === 'object' && value !== null
        ? cache.includes(value)
            ? undefined // Duplicate reference found, discard key
            : cache.push(value) && value // Store value in our collection
        : value,
    indent
  )
  cache = null
  return retVal
}