vercel/next.js · error

Unterminated string

Error message

Unterminated string

What it means

Thrown by tokenizeArgs when the args string finishes with an odd number of double-quote characters, meaning a quoted value was opened but never closed. The tokenizer tracks isInString and rejects an unbalanced quote at end of input.

Source

Thrown at packages/next/src/server/lib/utils.ts:111

    // If we find a quote, we should toggle the string flag.
    else if (char === '"') {
      isInString = !isInString
      continue
    }

    // If we're starting a new argument, we should add it to the array.
    if (willStartNewArg) {
      args.push(char)
      willStartNewArg = false
    }
    // Otherwise, add it to the last argument.
    else {
      args[args.length - 1] += char
    }
  }

  if (isInString) {
    throw new Error('Unterminated string')
  }

  return args
}

/**
 * Get the node options from the environment variable `NODE_OPTIONS` and returns
 * them as an array of strings.
 *
 * @returns An array of strings with the node options.
 */
export const getNodeOptionsArgs = () => {
  if (!process.env.NODE_OPTIONS) return []

  return tokenizeArgs(process.env.NODE_OPTIONS)
}

/**

View on GitHub (pinned to 0ae8c72462)

Solutions

1. Count the double-quotes in NODE_OPTIONS and ensure they are balanced (even count).
2. Properly close every opened quote, e.g. change --title="app to --title="app".
3. If the value has no spaces, remove the quotes entirely.

Example fix

# before: unclosed quote
export NODE_OPTIONS='--title="my app'

# after: balanced quotes
export NODE_OPTIONS='--title="my app"'

function hasBalancedQuotes(input: string): boolean {
  return (input.match(/"/g) || []).length % 2 === 0
}

function hasBalancedQuotes(input: string): boolean {
  return (input.match(/"/g) || []).length % 2 === 0
}

try {
  tokenizeArgs(process.env.NODE_OPTIONS || '')
} catch (e) {
  if (e.message === 'Unterminated string') {
    console.error('NODE_OPTIONS has an unbalanced quote')
    process.exit(1)
  }
}

When it happens

Trigger: NODE_OPTIONS contains a value with an opening quote but no closing quote, e.g. NODE_OPTIONS='--title="my app'. After the loop isInString is still true.

Common situations: Shell quoting mistakes in NODE_OPTIONS, a quote accidentally stripped by variable expansion, or copy-pasting a value that lost its closing quote.

Related errors

• Invalid escape character at the end.
• Unknown option: --${rawKey}
• Invalid --top value: ${topRaw}
• Invalid numeric value for --${key}: ${value}
• --routes cannot be empty

AI-assisted analysis of vercel/next.js@0ae8c72462 (2026-08-06). Data as JSON: /api/errors/7b81bc981d23e2b7. Report an issue: GitHub.