substance/test/collab/DocumentEngine.test.js

Substance is a JavaScript library for web-based content editing. It provides building blocks for realizing custom text editors and web-based publishing systems.

/* eslint-disable consistent-return */
import { module } from 'substance-test'
import { DocumentEngine } from 'substance'
import makeStoresFixture from './makeStoresFixture'

const test = module('collab/DocumentEngine')

/*
  TODO: Test documentEngine.deleteDocument, which removes clears all changes
        and snapshots
*/

test('Should allow creation of a new document', function(t) {
  let documentEngine = _fixture(0) // 0 changes, no snapshots
  let initialChange = _getChange(1)

  documentEngine.createDocument('test-doc', initialChange, function(err, newVersion) {
    t.notOk(err, 'Should not error')
    t.equal(newVersion, 1, 'Initial version should be 1')
    documentEngine.getDocument('test-doc', (err, snapshot, headVersion) => {
      t.ok(snapshot, 'Should have a snaphot')
      t.equal(headVersion, 1, 'Head version should be 1')
      t.end()
    })
  })
})

test('Should allow adding a new change', function(t) {
  let documentEngine = _fixture(2) // 0 changes, no snapshots
  let newChange = _getChange(3)

  documentEngine.addChange('test-doc', newChange, function(err, newVersion) {
    t.notOk(err, 'Should not error')
    t.equal(newVersion, 3, 'New version should be 3')
    documentEngine.getDocument('test-doc', (err, snapshot, headVersion) => {
      t.ok(snapshot, 'Should have a snaphot')
      t.equal(headVersion, 3, 'Latest snapshot version should be 3')
      t.end()
    })
  })
})


test('Should be able to retrieve changes', function(t) {
  let documentEngine = _fixture(2) // 0 changes, no snapshots
  documentEngine.getChanges('test-doc', function(err, changes) {
    t.equal(changes.length, 2, 'Should have two changes')
    t.end()
  })
})

/*
  'test-doc' with numChanges changes and available snapshots

  @param {Number} numChanges number of available changes
  @param {Number[]} snapshots an array of version numbers
*/
function _fixture(numChanges, snapshots) {
  let stores = makeStoresFixture(numChanges, snapshots)
  let documentEngine = new DocumentEngine({
    changeStore: stores.changeStore,
    snapshotStore: stores.snapshotStore,
    snapshotFrequency: 1 // store snapshots for each version
  })
  return documentEngine
}

/*
  Compute a valid change
*/
function _getChange(changeNum) {
  let stores = makeStoresFixture(changeNum)
  return stores.changeStore._changes['test-doc'][changeNum-1]
}