MZC/KnowMathBot/frontend/node_modules/mdast-util-to-markdown/lib/util/track.js

/**
 * @import {CreateTracker, TrackCurrent, TrackMove, TrackShift} from '../types.js'
 */

/**
 * Track positional info in the output.
 *
 * @type {CreateTracker}
 */
export function track(config) {
  // Defaults are used to prevent crashes when older utilities somehow activate
  // this code.
  /* c8 ignore next 5 */
  const options = config || {}
  const now = options.now || {}
  let lineShift = options.lineShift || 0
  let line = now.line || 1
  let column = now.column || 1

  return {move, current, shift}

  /**
   * Get the current tracked info.
   *
   * @type {TrackCurrent}
   */
  function current() {
    return {now: {line, column}, lineShift}
  }

  /**
   * Define an increased line shift (the typical indent for lines).
   *
   * @type {TrackShift}
   */
  function shift(value) {
    lineShift += value
  }

  /**
   * Move past some generated markdown.
   *
   * @type {TrackMove}
   */
  function move(input) {
    // eslint-disable-next-line unicorn/prefer-default-parameters
    const value = input || ''
    const chunks = value.split(/\r?\n|\r/g)
    const tail = chunks[chunks.length - 1]
    line += chunks.length - 1
    column =
      chunks.length === 1 ? column + tail.length : 1 + tail.length + lineShift
    return value
  }
}