yjs_testcase.ts

import * as Y from 'yjs'

const makeYDoc = (clientId: number) => {
  const doc = new Y.Doc()
  doc.clientID = clientId
  return doc
}

const yjsMergeInto = (target: Y.Doc, src: Y.Doc) => {
  const sv = Y.encodeStateVector(target)
  const update = Y.encodeStateAsUpdateV2(src, sv)
  Y.applyUpdateV2(target, update)
}


const a = makeYDoc(1)
a.getArray().insert(0, ['a']) // doca is ['a']
const b = makeYDoc(3)
b.getArray().insert(0, ['b']) // docb is ['b']


const c = makeYDoc(0)
yjsMergeInto(c, a)
yjsMergeInto(c, b)

c.getArray().insert(1, ['c'])
// docc inserts 'c' between 'a' and 'b' -> ['a', 'c', 'b']

a.getArray().insert(1, ['a1']) // a is ['a', 'a1']

b.getArray().insert(0, ['b0']) // b is ['b0', 'b']

/// If we merge everything together...
yjsMergeInto(a, b)
yjsMergeInto(a, c)
console.log(a.getArray().toArray()) // What should the order be?