export function xliffSerializePattern()

in js/src/xliff-serialize.ts [20:69]
50 lines of code
22 McCabe index (conditional complexity)

export function xliffSerializePattern(
  pattern: Pattern,
  onError: (error: SerializeError) => void
): string {
  const doc = new DOMParser().parseFromString('<target></target>', 'text/xml')
  const root = doc.querySelector('target')!
  let node = root
  for (const part of pattern) {
    if (typeof part === 'string') {
      appendText(node, part)
    } else if (part.open || part.elem) {
      const name = part.open || part.elem!
      const child = doc.createElementNS(null, name)
      for (const error of setAttributes(child, part.opt)) {
        onError(new SerializeError(`xliff: ${error}`))
      }
      node.appendChild(child)
      if (part.open) node = child
    } else if (part.close) {
      if (part.opt && Object.keys(part.opt).length) {
        const error = `xliff: Options on closing markup are not supported: ${JSON.stringify(part)}`
        onError(new SerializeError(error))
      }
      if (node !== root && node.tagName === part.close && node.parentElement) {
        node = node.parentElement
      } else {
        const error = `xliff: Improper element nesting for <${node.tagName}>`
        onError(new SerializeError(error))
      }
    } else if (typeof part.attr?.source === 'string') {
      appendText(node, part.attr.source)
    } else if (part._ || part.$) {
      appendText(node, part._ || part.$!)
    } else {
      const error = `xliff: Unsupported pattern part ${JSON.stringify(part)}`
      onError(new SerializeError(error))
      appendText(node, ERROR_RESULT)
    }
  }
  if (node !== root) {
    const error = `xliff: Missing closing markup for <${node.tagName}>`
    onError(new SerializeError(error))
  }
  try {
    return serialize(root)
  } catch (error) {
    onError(new SerializeError(`xliff: ${error}`))
    return ERROR_RESULT
  }
}