@atlaskit/editor-plugin-show-diff/dist/cjs/pm-plugins/calculateDiff/isMarkOnlyChange.js

ShowDiff plugin for @atlaskit/editor-core

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.isMarkOnlyChange = void 0;
/** U+0000 cannot occur in ProseMirror text content, so this cannot collide with document text. */
var NODE_MARKER = "\0";

/**
 * Node types and text only; marks and attrs excluded.
 *
 * Text is unprefixed so adjacent runs concatenate — a run only splits because its marks differ, so
 * `strong("hello")` and `strong("hel") + em("lo")` must match. Attrs are excluded because a
 * reconstructed agent edit regenerates `localId`s; `getAttrChangeRanges` reports attrs separately.
 */
var markFreeSignature = function markFreeSignature(doc, from, to) {
  var parts = [];
  doc.nodesBetween(from, to, function (node, pos) {
    if (node.isText) {
      var _node$text;
      var start = Math.max(pos, from) - pos;
      var end = Math.min(pos + node.nodeSize, to) - pos;
      parts.push(((_node$text = node.text) !== null && _node$text !== void 0 ? _node$text : '').slice(start, end));
    } else {
      parts.push("".concat(NODE_MARKER).concat(node.type.name));
    }
    return true;
  });
  return parts.join('');
};

/**
 * Whether a change differs only in marks, with identical structure and text on both sides. Only
 * produced when a mark-aware token encoder is in use.
 */
var isMarkOnlyChange = exports.isMarkOnlyChange = function isMarkOnlyChange(_ref) {
  var change = _ref.change,
    newDoc = _ref.newDoc,
    originalDoc = _ref.originalDoc;
  var fromA = change.fromA,
    toA = change.toA,
    fromB = change.fromB,
    toB = change.toB;
  var isPureInsertionOrDeletion = toA === fromA || toB === fromB;
  if (isPureInsertionOrDeletion || toA - fromA !== toB - fromB) {
    return false;
  }
  return markFreeSignature(originalDoc, fromA, toA) === markFreeSignature(newDoc, fromB, toB);
};