@mapbox/jsxtreme-markdown/vendor/remark-parse/lib/tokenize/thematic-break.js

Transform Markdown into JSX or React component modules

'use strict';

module.exports = thematicBreak;

var tab = '\t';
var lineFeed = '\n';
var space = ' ';
var asterisk = '*';
var dash = '-';
var underscore = '_';

var maxCount = 3;

function thematicBreak(eat, value, silent) {
  var index = -1;
  var length = value.length + 1;
  var subvalue = '';
  var character;
  var marker;
  var markerCount;
  var queue;

  while (++index < length) {
    character = value.charAt(index);

    if (character !== tab && character !== space) {
      break;
    }

    subvalue += character;
  }

  if (
    character !== asterisk &&
    character !== dash &&
    character !== underscore
  ) {
    return;
  }

  marker = character;
  subvalue += character;
  markerCount = 1;
  queue = '';

  while (++index < length) {
    character = value.charAt(index);

    if (character === marker) {
      markerCount++;
      subvalue += queue + marker;
      queue = '';
    } else if (character === space) {
      queue += character;
    } else if (
      markerCount >= maxCount &&
      (!character || character === lineFeed)
    ) {
      subvalue += queue;

      if (silent) {
        return true;
      }

      return eat(subvalue)({ type: 'thematicBreak' });
    } else {
      return;
    }
  }
}