Function HS

index.js:218–296

(futureNodes, futureStart, futureEnd, futureChanges, currentNodes, currentStart, currentEnd, currentChanges)

  var SKIP_OND = 50;

  var HS = function HS(futureNodes, futureStart, futureEnd, futureChanges, currentNodes, currentStart, currentEnd, currentChanges) {
    var k = 0;
    /* istanbul ignore next */

    var minLen = futureChanges < currentChanges ? futureChanges : currentChanges;
    var link = Array(minLen++);
    var tresh = Array(minLen);
    tresh[0] = -1;

    for (var i = 1; i < minLen; i++) {
      tresh[i] = currentEnd;
    }

    var nodes = currentNodes.slice(currentStart, currentEnd);

    for (var _i = futureStart; _i < futureEnd; _i++) {
      var index = nodes.indexOf(futureNodes[_i]);

      if (-1 < index) {
        var idxInOld = index + currentStart;
        k = findK(tresh, minLen, idxInOld);
        /* istanbul ignore else */

        if (-1 < k) {
          tresh[k] = idxInOld;
          link[k] = {
            newi: _i,
            oldi: idxInOld,
            prev: link[k - 1]
          };
        }
      }
    }

    k = --minLen;
    --currentEnd;

    while (tresh[k] > currentEnd) {
      --k;
    }

    minLen = currentChanges + futureChanges - k;
    var diff = Array(minLen);
    var ptr = link[k];
    --futureEnd;

    while (ptr) {
      var _ptr = ptr,
          newi = _ptr.newi,
          oldi = _ptr.oldi;

      while (futureEnd > newi) {
        diff[--minLen] = INSERTION;
        --futureEnd;
      }

      while (currentEnd > oldi) {
        diff[--minLen] = DELETION;