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

ShowDiff plugin for @atlaskit/editor-core

"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.smartChangeLevel = exports.rangesOverlap = exports.mergeOverlappingByNewDocRange = exports.makePromotedChange = exports.createSpans = void 0;
var _defineProperty2 = _interopRequireDefault(require("@babel/runtime/helpers/defineProperty"));
var _typeof2 = _interopRequireDefault(require("@babel/runtime/helpers/typeof"));
var _toConsumableArray2 = _interopRequireDefault(require("@babel/runtime/helpers/toConsumableArray"));
function ownKeys(e, r) { var t = Object.keys(e); if (Object.getOwnPropertySymbols) { var o = Object.getOwnPropertySymbols(e); r && (o = o.filter(function (r) { return Object.getOwnPropertyDescriptor(e, r).enumerable; })), t.push.apply(t, o); } return t; }
function _objectSpread(e) { for (var r = 1; r < arguments.length; r++) { var t = null != arguments[r] ? arguments[r] : {}; r % 2 ? ownKeys(Object(t), !0).forEach(function (r) { (0, _defineProperty2.default)(e, r, t[r]); }) : Object.getOwnPropertyDescriptors ? Object.defineProperties(e, Object.getOwnPropertyDescriptors(t)) : ownKeys(Object(t)).forEach(function (r) { Object.defineProperty(e, r, Object.getOwnPropertyDescriptor(t, r)); }); } return e; }
function _createForOfIteratorHelper(r, e) { var t = "undefined" != typeof Symbol && r[Symbol.iterator] || r["@@iterator"]; if (!t) { if (Array.isArray(r) || (t = _unsupportedIterableToArray(r)) || e && r && "number" == typeof r.length) { t && (r = t); var _n = 0, F = function F() {}; return { s: F, n: function n() { return _n >= r.length ? { done: !0 } : { done: !1, value: r[_n++] }; }, e: function e(r) { throw r; }, f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } var o, a = !0, u = !1; return { s: function s() { t = t.call(r); }, n: function n() { var r = t.next(); return a = r.done, r; }, e: function e(r) { u = !0, o = r; }, f: function f() { try { a || null == t.return || t.return(); } finally { if (u) throw o; } } }; }
function _unsupportedIterableToArray(r, a) { if (r) { if ("string" == typeof r) return _arrayLikeToArray(r, a); var t = {}.toString.call(r).slice(8, -1); return "Object" === t && r.constructor && (t = r.constructor.name), "Map" === t || "Set" === t ? Array.from(r) : "Arguments" === t || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(t) ? _arrayLikeToArray(r, a) : void 0; } }
function _arrayLikeToArray(r, a) { (null == a || a > r.length) && (a = r.length); for (var e = 0, n = Array(a); e < a; e++) n[e] = r[e]; return n; }
/**
 * The granularity level a `smart` change was promoted to. Stored on span `data` so the
 * decoration pipeline can render each level differently (e.g. node-level deletions shown
 * below the new content). `null` for non-promoted (inline) changes.
 */

/** Span `data` payload carried by promoted `smart` changes. */

/**
 * Build the `deleted`/`inserted` span arrays a `Change` needs. A length of 0 yields an
 * empty array (no change on that side).
 */
var createSpans = exports.createSpans = function createSpans(length) {
  var data = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : null;
  return length > 0 ? [{
    length: length,
    data: data
  }] : [];
};

/**
 * Build a promoted `Change` spanning `[fromA,toA)` in the original doc and `[fromB,toB)`
 * in the new doc, with both sides marked changed (mirrors `groupChangesByBlock` so the
 * decoration pipeline renders both the inserted-block decoration and the deleted-node
 * widget).
 *
 * `level` tags the change's spans so downstream decoration logic can treat node-level
 * promotions specially (see `smartChangeLevel`).
 */
var makePromotedChange = exports.makePromotedChange = function makePromotedChange(fromA, toA, fromB, toB, level) {
  var data = level ? {
    smartLevel: level
  } : null;
  // `deleted` and `inserted` must be independent arrays: downstream code may mutate one
  // side (push/splice), which would silently corrupt the other if they shared a reference.
  return {
    fromA: fromA,
    toA: toA,
    fromB: fromB,
    toB: toB,
    deleted: createSpans(Math.max(0, toA - fromA), data),
    inserted: createSpans(Math.max(0, toB - fromB), data)
  };
};

/**
 * Read the `smartLevel` tag off a change's spans, if present. Returns `undefined` for
 * changes not produced by the `smart` classifier (e.g. inline/block/step diff types).
 */
var smartChangeLevel = exports.smartChangeLevel = function smartChangeLevel(change) {
  var spans = [].concat((0, _toConsumableArray2.default)(change.inserted), (0, _toConsumableArray2.default)(change.deleted));
  var _iterator = _createForOfIteratorHelper(spans),
    _step;
  try {
    for (_iterator.s(); !(_step = _iterator.n()).done;) {
      var span = _step.value;
      var data = span.data;
      if (data && (0, _typeof2.default)(data) === 'object' && 'smartLevel' in data) {
        return data.smartLevel;
      }
    }
  } catch (err) {
    _iterator.e(err);
  } finally {
    _iterator.f();
  }
  return undefined;
};

/** True when a change has no original-side (deleted) content — a pure insertion. */
var isPureInsertion = function isPureInsertion(change) {
  return change.toA <= change.fromA;
};

/**
 * Coalesce changes that overlap in new-doc (B) coordinates.
 *
 * Merging two changes takes the UNION of their A (original-doc) ranges. That is only safe when
 * their A ranges actually touch/overlap — OR when at least one is a pure insertion (empty A).
 * Otherwise, merging a deletion at A[110,152] with a later edit at A[162,168] would fabricate an
 * A span [110,168] covering the untouched gap, which then overlaps a *different* change's A range
 * (making the same original content appear deleted twice). So we require B-overlap AND
 * (A-overlap OR a pure insertion) before coalescing.
 */
var mergeOverlappingByNewDocRange = exports.mergeOverlappingByNewDocRange = function mergeOverlappingByNewDocRange(changes) {
  if (changes.length <= 1) {
    return changes;
  }
  var sorted = (0, _toConsumableArray2.default)(changes).sort(function (l, r) {
    return l.fromB - r.fromB;
  });
  var merged = [];
  var current = _objectSpread({}, sorted[0]);
  for (var i = 1; i < sorted.length; i++) {
    var next = sorted[i];
    var bOverlaps = next.fromB <= current.toB;
    // A ranges may be unioned only if they touch, or if either side contributes no A content.
    var aMergeable = isPureInsertion(current) || isPureInsertion(next) || rangesOverlap(current.fromA, current.toA, next.fromA, next.toA) || next.fromA <= current.toA; // adjacency (sorted by B, A usually monotonic)
    if (bOverlaps && aMergeable) {
      current = {
        fromA: Math.min(current.fromA, next.fromA),
        toA: Math.max(current.toA, next.toA),
        fromB: Math.min(current.fromB, next.fromB),
        toB: Math.max(current.toB, next.toB),
        deleted: [].concat((0, _toConsumableArray2.default)(current.deleted), (0, _toConsumableArray2.default)(next.deleted)),
        inserted: [].concat((0, _toConsumableArray2.default)(current.inserted), (0, _toConsumableArray2.default)(next.inserted))
      };
    } else {
      merged.push(current);
      current = _objectSpread({}, next);
    }
  }
  merged.push(current);
  return merged;
};

/** True when two half-open ranges overlap. */
var rangesOverlap = exports.rangesOverlap = function rangesOverlap(aFrom, aTo, bFrom, bTo) {
  return aFrom < bTo && bFrom < aTo;
};