yjs#667 - add sanity messages when data is read before type is added to a document.

Author: dmonad

src/types/AbstractType.js

@@ -17,6 +17,12 @@ import * as map from 'lib0/map'
 import * as iterator from 'lib0/iterator'
 import * as error from 'lib0/error'
 import * as math from 'lib0/math'
+import * as log from 'lib0/logging'
+
+/**
+ * https://docs.yjs.dev/getting-started/working-with-shared-types#caveats
+ */
+export const warnPrematureAccess = () => { log.warn('Invalid access: Add Yjs type to a document before reading data.') }
 
 const maxSearchMarker = 80
 
@@ -215,6 +221,7 @@ export const updateMarkerChanges = (searchMarker, index, len) => {
  * @return {Array<Item>}
  */
 export const getTypeChildren = t => {
+  t.doc ?? warnPrematureAccess()
   let s = t._start
   const arr = []
   while (s) {
@@ -408,6 +415,7 @@ export class AbstractType {
  * @function
  */
 export const typeListSlice = (type, start, end) => {
+  type.doc ?? warnPrematureAccess()
   if (start < 0) {
     start = type._length + start
   }
@@ -443,6 +451,7 @@ export const typeListSlice = (type, start, end) => {
  * @function
  */
 export const typeListToArray = type => {
+  type.doc ?? warnPrematureAccess()
   const cs = []
   let n = type._start
   while (n !== null) {
@@ -492,6 +501,7 @@ export const typeListToArraySnapshot = (type, snapshot) => {
 export const typeListForEach = (type, f) => {
   let index = 0
   let n = type._start
+  type.doc ?? warnPrematureAccess()
   while (n !== null) {
     if (n.countable && !n.deleted) {
       const c = n.content.getContent()
@@ -606,6 +616,7 @@ export const typeListForEachSnapshot = (type, f, snapshot) => {
  * @function
  */
 export const typeListGet = (type, index) => {
+  type.doc ?? warnPrematureAccess()
   const marker = findMarker(type, index)
   let n = type._start
   if (marker !== null) {
@@ -874,6 +885,7 @@ export const typeMapSet = (transaction, parent, key, value) => {
  * @function
  */
 export const typeMapGet = (parent, key) => {
+  parent.doc ?? warnPrematureAccess()
   const val = parent._map.get(key)
   return val !== undefined && !val.deleted ? val.content.getContent()[val.length - 1] : undefined
 }
@@ -890,6 +902,7 @@ export const typeMapGetAll = (parent) => {
    * @type {Object<string,any>}
    */
   const res = {}
+  parent.doc ?? warnPrematureAccess()
   parent._map.forEach((value, key) => {
     if (!value.deleted) {
       res[key] = value.content.getContent()[value.length - 1]
@@ -907,6 +920,7 @@ export const typeMapGetAll = (parent) => {
  * @function
  */
 export const typeMapHas = (parent, key) => {
+  parent.doc ?? warnPrematureAccess()
   const val = parent._map.get(key)
   return val !== undefined && !val.deleted
 }
@@ -957,10 +971,13 @@ export const typeMapGetAllSnapshot = (parent, snapshot) => {
 }
 
 /**
- * @param {Map<string,Item>} map
+ * @param {AbstractType<any> & { _map: Map<string, Item> }} type
  * @return {IterableIterator<Array<any>>}
  *
  * @private
  * @function
  */
-export const createMapIterator = map => iterator.iteratorFilter(map.entries(), /** @param {any} entry */ entry => !entry[1].deleted)
+export const createMapIterator = type => {
+  type.doc ?? warnPrematureAccess()
+  return iterator.iteratorFilter(type._map.entries(), /** @param {any} entry */ entry => !entry[1].deleted)
+}

src/types/YArray.js

@@ -16,6 +16,7 @@ import {
   YArrayRefID,
   callTypeObservers,
   transact,
+  warnPrematureAccess,
   ArraySearchMarker, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Transaction, Item // eslint-disable-line
 } from '../internals.js'
 import { typeListSlice } from './AbstractType.js'
@@ -104,6 +105,7 @@ export class YArray extends AbstractType {
   }
 
   get length () {
+    this.doc ?? warnPrematureAccess()
     return this._length
   }
 

src/types/YMap.js

@@ -13,6 +13,7 @@ import {
   YMapRefID,
   callTypeObservers,
   transact,
+  warnPrematureAccess,
   UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, Transaction, Item // eslint-disable-line
 } from '../internals.js'
 
@@ -121,6 +122,7 @@ export class YMap extends AbstractType {
    * @return {Object<string,any>}
    */
   toJSON () {
+    this.doc ?? warnPrematureAccess()
     /**
      * @type {Object<string,MapType>}
      */
@@ -140,7 +142,7 @@ export class YMap extends AbstractType {
    * @return {number}
    */
   get size () {
-    return [...createMapIterator(this._map)].length
+    return [...createMapIterator(this)].length
   }
 
   /**
@@ -149,7 +151,7 @@ export class YMap extends AbstractType {
    * @return {IterableIterator<string>}
    */
   keys () {
-    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => v[0])
+    return iterator.iteratorMap(createMapIterator(this), /** @param {any} v */ v => v[0])
   }
 
   /**
@@ -158,7 +160,7 @@ export class YMap extends AbstractType {
    * @return {IterableIterator<MapType>}
    */
   values () {
-    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => v[1].content.getContent()[v[1].length - 1])
+    return iterator.iteratorMap(createMapIterator(this), /** @param {any} v */ v => v[1].content.getContent()[v[1].length - 1])
   }
 
   /**
@@ -167,7 +169,7 @@ export class YMap extends AbstractType {
    * @return {IterableIterator<[string, MapType]>}
    */
   entries () {
-    return iterator.iteratorMap(createMapIterator(this._map), /** @param {any} v */ v => /** @type {any} */ ([v[0], v[1].content.getContent()[v[1].length - 1]]))
+    return iterator.iteratorMap(createMapIterator(this), /** @param {any} v */ v => /** @type {any} */ ([v[0], v[1].content.getContent()[v[1].length - 1]]))
   }
 
   /**
@@ -176,6 +178,7 @@ export class YMap extends AbstractType {
    * @param {function(MapType,string,YMap<MapType>):void} f A function to execute on every element of this YArray.
    */
   forEach (f) {
+    this.doc ?? warnPrematureAccess()
     this._map.forEach((item, key) => {
       if (!item.deleted) {
         f(item.content.getContent()[item.length - 1], key, this)

src/types/YText.js

@@ -26,6 +26,7 @@ import {
   typeMapGetAll,
   updateMarkerChanges,
   ContentType,
+  warnPrematureAccess,
   ArraySearchMarker, UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, ID, Doc, Item, Snapshot, Transaction // eslint-disable-line
 } from '../internals.js'
 
@@ -875,6 +876,7 @@ export class YText extends AbstractType {
    * @type {number}
    */
   get length () {
+    this.doc ?? warnPrematureAccess()
     return this._length
   }
 
@@ -931,6 +933,7 @@ export class YText extends AbstractType {
    * @public
    */
   toString () {
+    this.doc ?? warnPrematureAccess()
     let str = ''
     /**
      * @type {Item|null}
@@ -1004,6 +1007,7 @@ export class YText extends AbstractType {
    * @public
    */
   toDelta (snapshot, prevSnapshot, computeYChange) {
+    this.doc ?? warnPrematureAccess()
     /**
      * @type{Array<any>}
      */

src/types/YXmlFragment.js

@@ -17,6 +17,7 @@ import {
   transact,
   typeListGet,
   typeListSlice,
+  warnPrematureAccess,
   UpdateDecoderV1, UpdateDecoderV2, UpdateEncoderV1, UpdateEncoderV2, Doc, ContentType, Transaction, Item, YXmlText, YXmlHook // eslint-disable-line
 } from '../internals.js'
 
@@ -66,6 +67,7 @@ export class YXmlTreeWalker {
      */
     this._currentNode = /** @type {Item} */ (root._start)
     this._firstCall = true
+    root.doc ?? warnPrematureAccess()
   }
 
   [Symbol.iterator] () {
@@ -177,6 +179,7 @@ export class YXmlFragment extends AbstractType {
   }
 
   get length () {
+    this.doc ?? warnPrematureAccess()
     return this._prelimContent === null ? this._length : this._prelimContent.length
   }