@atlaskit/editor-plugin-show-diff/dist/esm/pm-plugins/calculateDiff/computeDiffChanges.js

ShowDiff plugin for @atlaskit/editor-core

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$/.test(t) ? _arrayLikeToArray(r, a) : void 0; } }
function _arrayLikeToArray(r, a) { (null == a || a > r.length) && (a = r.length); for (var e = 0, n = Array(a); e < a; e++) n[e] = r[e]; return n; }
/**
 * Generic, editor-state-free diff-change computation.
 *
 * Turns an `originalDoc` + forward `steps` into the classified `Change[]` for the
 * requested `diffType`, plus the reconstructed new document — the same classifier
 * the diff overlay uses (`calculateDiffDecorations` → `getChanges`), exposed as a
 * reusable utility (e.g. to derive reviewable segments without rendering
 * decorations). It runs the requested `diffType` DIRECTLY and does NOT apply the
 * overlay's `platform_editor_ai_smart_diff` gate, so a `smart` result here can
 * differ from what the overlay draws when that gate is off (the overlay falls back
 * to inline); callers that need overlay parity must account for that gate.
 *
 * Pure: no `EditorState`, no transactions, no React. The new document is
 * reconstructed by applying the (simplified) steps to `originalDoc`.
 */
import { ChangeSet, simplifyChanges } from 'prosemirror-changeset';
import { attrAwareTokenEncoder } from './attrAwareTokenEncoder';
import { diffBySteps } from './diffBySteps';
import { groupChangesByBlock } from './groupChangesByBlock';
import { optimizeChanges } from './optimizeChanges';
import { simplifySteps } from './simplifySteps';
import { classifySmartChanges } from './smart/classifySmartChanges';
/**
 * Apply the (simplified) steps to `originalDoc` to reconstruct the new doc, and
 * compute the classified `Change[]` for the requested `diffType`. Mirrors the
 * body of `calculateDiffDecorations` → `getChanges` so callers stay in lock-step
 * with the rendered diff. Returns an empty change list (and `originalDoc` as the
 * new doc) when there are no steps.
 */
export var computeDiffChanges = function computeDiffChanges(_ref) {
  var originalDoc = _ref.originalDoc,
    steps = _ref.steps,
    _ref$diffType = _ref.diffType,
    diffType = _ref$diffType === void 0 ? 'smart' : _ref$diffType,
    _ref$locale = _ref.locale,
    locale = _ref$locale === void 0 ? 'en' : _ref$locale,
    smartThresholds = _ref.smartThresholds;
  if (!steps || steps.length === 0) {
    return {
      changes: [],
      newDoc: originalDoc
    };
  }
  var simplifiedSteps = simplifySteps(steps, originalDoc);
  var steppedDoc = originalDoc;
  var stepMaps = [];
  try {
    var _iterator = _createForOfIteratorHelper(simplifiedSteps),
      _step;
    try {
      for (_iterator.s(); !(_step = _iterator.n()).done;) {
        var step = _step.value;
        var result = step.apply(steppedDoc);
        if (result.failed === null && result.doc) {
          stepMaps.push(step.getMap());
          steppedDoc = result.doc;
        }
      }
    } catch (err) {
      _iterator.e(err);
    } finally {
      _iterator.f();
    }
  } catch (_unused) {
    // A step's positions fell outside the current doc — `ReplaceStep.apply`
    // throws a RangeError (rather than returning a failed result) when a
    // position exceeds the doc size. This can happen for pathological or
    // inconsistent step sequences. Bail with no changes rather than letting the
    // error propagate to the caller (which, for the PSR, would crash the
    // toolbar); the consumer then falls back to its non-diff segmenting path.
    return {
      changes: [],
      newDoc: originalDoc
    };
  }

  // The attribute-aware encoder only affects the `smart` classification, so it is
  // applied only for that type. (This utility intentionally applies no feature
  // gate — see the file docstring — but a caller requesting `smart` is already
  // behind the smart-diff gate.)
  var tokenEncoder = diffType === 'smart' ? attrAwareTokenEncoder : undefined;
  var changeset = ChangeSet.create(originalDoc, undefined, tokenEncoder).addSteps(steppedDoc, stepMaps, steppedDoc);
  if (diffType === 'smart') {
    return {
      changes: classifySmartChanges({
        changes: simplifyChanges(changeset.changes, steppedDoc),
        originalDoc: originalDoc,
        newDoc: steppedDoc,
        locale: locale,
        thresholds: smartThresholds
      }),
      newDoc: steppedDoc
    };
  }
  if (diffType === 'block') {
    return {
      changes: groupChangesByBlock(changeset.changes, originalDoc, steppedDoc),
      newDoc: steppedDoc
    };
  }
  if (diffType === 'step') {
    return {
      changes: diffBySteps(originalDoc, simplifiedSteps),
      newDoc: steppedDoc
    };
  }
  return {
    changes: optimizeChanges(simplifyChanges(changeset.changes, steppedDoc)),
    newDoc: steppedDoc
  };
};