overleaf/services/document-updater/app/js/sharejs/text-api.js

// TODO: This file was created by bulk-decaffeinate.
// Sanity-check the conversion and remove this comment.
/*
 * decaffeinate suggestions:
 * DS101: Remove unnecessary use of Array.from
 * DS102: Remove unnecessary code created because of implicit returns
 * Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
 */
// Text document API for text

let text;
if (typeof WEB === 'undefined') { text = require('./text'); }

text.api = {
  provides: {text:true},

  // The number of characters in the string
  getLength() { return this.snapshot.length; },

  // Get the text contents of a document
  getText() { return this.snapshot; },

  insert(pos, text, callback) {
    const op = [{p:pos, i:text}];
    
    this.submitOp(op, callback);
    return op;
  },
  
  del(pos, length, callback) {
    const op = [{p:pos, d:this.snapshot.slice(pos, (pos + length))}];

    this.submitOp(op, callback);
    return op;
  },
  
  _register() {
    return this.on('remoteop', function(op) {
      return Array.from(op).map((component) =>
        component.i !== undefined ?
          this.emit('insert', component.p, component.i)
        :
          this.emit('delete', component.p, component.d));
    });
  }
};