lint

package.json

@@ -56,7 +56,7 @@
   },
   "homepage": "https://yjs.dev",
   "dependencies": {
-    "lib0": "^0.2.2"
+    "lib0": "^0.2.7"
   },
   "devDependencies": {
     "@rollup/plugin-commonjs": "^11.0.1",
@@ -65,11 +65,11 @@
     "http-server": "^0.12.1",
     "jsdoc": "^3.6.3",
     "markdownlint-cli": "^0.19.0",
-    "rollup": "^1.29.0",
+    "rollup": "^1.29.1",
     "rollup-cli": "^1.0.9",
-    "standard": "^11.0.1",
+    "standard": "^14.0.0",
     "tui-jsdoc-template": "^1.2.2",
-    "typescript": "^3.6.2",
+    "typescript": "^3.7.5",
     "y-protocols": "^0.2.0"
   }
 }

src/structs/AbstractStruct.js

@@ -24,6 +24,7 @@ export class AbstractStruct {
     this.length = length
     this.deleted = false
   }
+
   /**
    * Merge this struct with the item to the right.
    * This method is already assuming that `this.id.clock + this.length === this.id.clock`.
@@ -34,6 +35,7 @@ export class AbstractStruct {
   mergeWith (right) {
     return false
   }
+
   /**
    * @param {encoding.Encoder} encoder The encoder to write data to.
    * @param {number} offset
@@ -43,6 +45,7 @@ export class AbstractStruct {
   write (encoder, offset, encodingRef) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {Transaction} transaction
    */
@@ -69,6 +72,7 @@ export class AbstractStructRef {
      */
     this.id = id
   }
+
   /**
    * @param {Transaction} transaction
    * @return {Array<ID|null>}
@@ -76,6 +80,7 @@ export class AbstractStructRef {
   getMissing (transaction) {
     return this._missing
   }
+
   /**
    * @param {Transaction} transaction
    * @param {StructStore} store

src/structs/ContentAny.js

@@ -18,30 +18,35 @@ export class ContentAny {
      */
     this.arr = arr
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return this.arr.length
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return this.arr
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentAny}
    */
   copy () {
     return new ContentAny(this.arr)
   }
+
   /**
    * @param {number} offset
    * @return {ContentAny}
@@ -51,6 +56,7 @@ export class ContentAny {
     this.arr = this.arr.slice(0, offset)
     return right
   }
+
   /**
    * @param {ContentAny} right
    * @return {boolean}
@@ -59,6 +65,7 @@ export class ContentAny {
     this.arr = this.arr.concat(right.arr)
     return true
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -84,6 +91,7 @@ export class ContentAny {
       encoding.writeAny(encoder, c)
     }
   }
+
   /**
    * @return {number}
    */

src/structs/ContentBinary.js

@@ -17,30 +17,35 @@ export class ContentBinary {
   constructor (content) {
     this.content = content
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return 1
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return [this.content]
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentBinary}
    */
   copy () {
     return new ContentBinary(this.content)
   }
+
   /**
    * @param {number} offset
    * @return {ContentBinary}
@@ -48,6 +53,7 @@ export class ContentBinary {
   splice (offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {ContentBinary} right
    * @return {boolean}
@@ -55,6 +61,7 @@ export class ContentBinary {
   mergeWith (right) {
     return false
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -75,6 +82,7 @@ export class ContentBinary {
   write (encoder, offset) {
     encoding.writeVarUint8Array(encoder, this.content)
   }
+
   /**
    * @return {number}
    */

src/structs/ContentDeleted.js

@@ -17,30 +17,35 @@ export class ContentDeleted {
   constructor (len) {
     this.len = len
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return this.len
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return []
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return false
   }
+
   /**
    * @return {ContentDeleted}
    */
   copy () {
     return new ContentDeleted(this.len)
   }
+
   /**
    * @param {number} offset
    * @return {ContentDeleted}
@@ -50,6 +55,7 @@ export class ContentDeleted {
     this.len = offset
     return right
   }
+
   /**
    * @param {ContentDeleted} right
    * @return {boolean}
@@ -58,6 +64,7 @@ export class ContentDeleted {
     this.len += right.len
     return true
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -66,6 +73,7 @@ export class ContentDeleted {
     addToDeleteSet(transaction.deleteSet, item.id, this.len)
     item.deleted = true
   }
+
   /**
    * @param {Transaction} transaction
    */
@@ -81,6 +89,7 @@ export class ContentDeleted {
   write (encoder, offset) {
     encoding.writeVarUint(encoder, this.len - offset)
   }
+
   /**
    * @return {number}
    */

src/structs/ContentEmbed.js

@@ -17,30 +17,35 @@ export class ContentEmbed {
   constructor (embed) {
     this.embed = embed
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return 1
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return [this.embed]
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentEmbed}
    */
   copy () {
     return new ContentEmbed(this.embed)
   }
+
   /**
    * @param {number} offset
    * @return {ContentEmbed}
@@ -48,6 +53,7 @@ export class ContentEmbed {
   splice (offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {ContentEmbed} right
    * @return {boolean}
@@ -55,6 +61,7 @@ export class ContentEmbed {
   mergeWith (right) {
     return false
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -75,6 +82,7 @@ export class ContentEmbed {
   write (encoder, offset) {
     encoding.writeVarString(encoder, JSON.stringify(this.embed))
   }
+
   /**
    * @return {number}
    */

src/structs/ContentFormat.js

@@ -19,30 +19,35 @@ export class ContentFormat {
     this.key = key
     this.value = value
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return 1
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return []
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return false
   }
+
   /**
    * @return {ContentFormat}
    */
   copy () {
     return new ContentFormat(this.key, this.value)
   }
+
   /**
    * @param {number} offset
    * @return {ContentFormat}
@@ -50,6 +55,7 @@ export class ContentFormat {
   splice (offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {ContentFormat} right
    * @return {boolean}
@@ -57,6 +63,7 @@ export class ContentFormat {
   mergeWith (right) {
     return false
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -78,6 +85,7 @@ export class ContentFormat {
     encoding.writeVarString(encoder, this.key)
     encoding.writeVarString(encoder, JSON.stringify(this.value))
   }
+
   /**
    * @return {number}
    */

src/structs/ContentJSON.js

@@ -18,30 +18,35 @@ export class ContentJSON {
      */
     this.arr = arr
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return this.arr.length
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return this.arr
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentJSON}
    */
   copy () {
     return new ContentJSON(this.arr)
   }
+
   /**
    * @param {number} offset
    * @return {ContentJSON}
@@ -51,6 +56,7 @@ export class ContentJSON {
     this.arr = this.arr.slice(0, offset)
     return right
   }
+
   /**
    * @param {ContentJSON} right
    * @return {boolean}
@@ -59,6 +65,7 @@ export class ContentJSON {
     this.arr = this.arr.concat(right.arr)
     return true
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -84,6 +91,7 @@ export class ContentJSON {
       encoding.writeVarString(encoder, c === undefined ? 'undefined' : JSON.stringify(c))
     }
   }
+
   /**
    * @return {number}
    */

src/structs/ContentString.js

@@ -18,30 +18,35 @@ export class ContentString {
      */
     this.str = str
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return this.str.length
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return this.str.split('')
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentString}
    */
   copy () {
     return new ContentString(this.str)
   }
+
   /**
    * @param {number} offset
    * @return {ContentString}
@@ -51,6 +56,7 @@ export class ContentString {
     this.str = this.str.slice(0, offset)
     return right
   }
+
   /**
    * @param {ContentString} right
    * @return {boolean}
@@ -59,6 +65,7 @@ export class ContentString {
     this.str += right.str
     return true
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -79,6 +86,7 @@ export class ContentString {
   write (encoder, offset) {
     encoding.writeVarString(encoder, offset === 0 ? this.str : this.str.slice(offset))
   }
+
   /**
    * @return {number}
    */

src/structs/ContentType.js

@@ -49,30 +49,35 @@ export class ContentType {
      */
     this.type = type
   }
+
   /**
    * @return {number}
    */
   getLength () {
     return 1
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     return [this.type]
   }
+
   /**
    * @return {boolean}
    */
   isCountable () {
     return true
   }
+
   /**
    * @return {ContentType}
    */
   copy () {
     return new ContentType(this.type._copy())
   }
+
   /**
    * @param {number} offset
    * @return {ContentType}
@@ -80,6 +85,7 @@ export class ContentType {
   splice (offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {ContentType} right
    * @return {boolean}
@@ -87,6 +93,7 @@ export class ContentType {
   mergeWith (right) {
     return false
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -94,6 +101,7 @@ export class ContentType {
   integrate (transaction, item) {
     this.type._integrate(transaction.doc, item)
   }
+
   /**
    * @param {Transaction} transaction
    */
@@ -121,6 +129,7 @@ export class ContentType {
     })
     transaction.changed.delete(this.type)
   }
+
   /**
    * @param {StructStore} store
    */
@@ -139,6 +148,7 @@ export class ContentType {
     })
     this.type._map = new Map()
   }
+
   /**
    * @param {encoding.Encoder} encoder
    * @param {number} offset
@@ -146,6 +156,7 @@ export class ContentType {
   write (encoder, offset) {
     this.type._write(encoder)
   }
+
   /**
    * @return {number}
    */

src/structs/GC.js

@@ -69,6 +69,7 @@ export class GCRef extends AbstractStructRef {
      */
     this.length = decoding.readVarUint(decoder)
   }
+
   /**
    * @param {Transaction} transaction
    * @param {StructStore} store

src/structs/Item.js

@@ -430,6 +430,7 @@ export class Item extends AbstractStruct {
   get lastId () {
     return createID(this.id.client, this.id.clock + this.length - 1)
   }
+
   /**
    * Try to merge two items
    *
@@ -578,12 +579,14 @@ export class AbstractContent {
   getLength () {
     throw error.methodUnimplemented()
   }
+
   /**
    * @return {Array<any>}
    */
   getContent () {
     throw error.methodUnimplemented()
   }
+
   /**
    * Should return false if this Item is some kind of meta information
    * (e.g. format information).
@@ -596,12 +599,14 @@ export class AbstractContent {
   isCountable () {
     throw error.methodUnimplemented()
   }
+
   /**
    * @return {AbstractContent}
    */
   copy () {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {number} offset
    * @return {AbstractContent}
@@ -609,6 +614,7 @@ export class AbstractContent {
   splice (offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {AbstractContent} right
    * @return {boolean}
@@ -616,6 +622,7 @@ export class AbstractContent {
   mergeWith (right) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {Transaction} transaction
    * @param {Item} item
@@ -623,18 +630,21 @@ export class AbstractContent {
   integrate (transaction, item) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {Transaction} transaction
    */
   delete (transaction) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {StructStore} store
    */
   gc (store) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @param {encoding.Encoder} encoder
    * @param {number} offset
@@ -642,6 +652,7 @@ export class AbstractContent {
   write (encoder, offset) {
     throw error.methodUnimplemented()
   }
+
   /**
    * @return {number}
    */
@@ -709,6 +720,7 @@ export class ItemRef extends AbstractStructRef {
     this.content = readItemContent(decoder, info)
     this.length = this.content.getLength()
   }
+
   /**
    * @param {Transaction} transaction
    * @param {StructStore} store

src/types/AbstractType.js

@@ -171,7 +171,7 @@ export class AbstractType {
 
   /**
    * @abstract
-   * @return {Object | Array | number | string}
+   * @return {any}
    */
   toJSON () {}
 }
@@ -370,7 +370,7 @@ export const typeListInsertGenericsAfter = (transaction, parent, referenceItem,
   let left = referenceItem
   const right = referenceItem === null ? parent._start : referenceItem.right
   /**
-   * @type {Array<Object|Array|number>}
+   * @type {Array<Object|Array<any>|number>}
    */
   let jsonContent = []
   const packJsonContent = () => {
@@ -515,7 +515,7 @@ export const typeMapSet = (transaction, parent, key, value) => {
         content = new ContentAny([value])
         break
       case Uint8Array:
-        content = new ContentBinary(value)
+        content = new ContentBinary(/** @type {Uint8Array} */ (value))
         break
       default:
         if (value instanceof AbstractType) {
@@ -552,7 +552,7 @@ export const typeMapGetAll = (parent) => {
   /**
    * @type {Object<string,any>}
    */
-  let res = {}
+  const res = {}
   for (const [key, value] of parent._map) {
     if (!value.deleted) {
       res[key] = value.content.getContent()[value.length - 1]

src/types/YArray.js

@@ -51,6 +51,7 @@ export class YArray extends AbstractType {
      */
     this._prelimContent = []
   }
+
   /**
    * Integrate this type into the Yjs instance.
    *
@@ -65,7 +66,7 @@ export class YArray extends AbstractType {
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    this.insert(0, /** @type {Array} */ (this._prelimContent))
+    this.insert(0, /** @type {Array<any>} */ (this._prelimContent))
     this._prelimContent = null
   }
 
@@ -76,6 +77,7 @@ export class YArray extends AbstractType {
   get length () {
     return this._prelimContent === null ? this._length : this._prelimContent.length
   }
+
   /**
    * Creates YArrayEvent and calls observers.
    *
@@ -110,7 +112,7 @@ export class YArray extends AbstractType {
         typeListInsertGenerics(transaction, this, index, content)
       })
     } else {
-      /** @type {Array} */ (this._prelimContent).splice(index, 0, ...content)
+      /** @type {Array<any>} */ (this._prelimContent).splice(index, 0, ...content)
     }
   }
 
@@ -135,7 +137,7 @@ export class YArray extends AbstractType {
         typeListDelete(transaction, this, index, length)
       })
     } else {
-      /** @type {Array} */ (this._prelimContent).splice(index, length)
+      /** @type {Array<any>} */ (this._prelimContent).splice(index, length)
     }
   }
 

src/types/YMap.js

@@ -53,6 +53,7 @@ export class YMap extends AbstractType {
      */
     this._prelimContent = new Map()
   }
+
   /**
    * Integrate this type into the Yjs instance.
    *
@@ -67,7 +68,7 @@ export class YMap extends AbstractType {
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    for (let [key, value] of /** @type {Map<string, any>} */ (this._prelimContent)) {
+    for (const [key, value] of /** @type {Map<string, any>} */ (this._prelimContent)) {
       this.set(key, value)
     }
     this._prelimContent = null
@@ -99,7 +100,7 @@ export class YMap extends AbstractType {
      * @type {Object<string,T>}
      */
     const map = {}
-    for (let [key, item] of this._map) {
+    for (const [key, item] of this._map) {
       if (!item.deleted) {
         const v = item.content.getContent()[item.length - 1]
         map[key] = v instanceof AbstractType ? v.toJSON() : v
@@ -145,7 +146,7 @@ export class YMap extends AbstractType {
      * @type {Object<string,T>}
      */
     const map = {}
-    for (let [key, item] of this._map) {
+    for (const [key, item] of this._map) {
       if (!item.deleted) {
         f(item.content.getContent()[item.length - 1], key, this)
       }

src/types/YText.js

@@ -112,10 +112,9 @@ const findNextPosition = (transaction, currentAttributes, left, right, count) =>
  * @function
  */
 const findPosition = (transaction, parent, index) => {
-  let currentAttributes = new Map()
+  const currentAttributes = new Map()
-  let left = null
+  const right = parent._start
-  let right = parent._start
+  return findNextPosition(transaction, currentAttributes, null, right, index)
-  return findNextPosition(transaction, currentAttributes, left, right, index)
 }
 
 /**
@@ -147,7 +146,7 @@ const insertNegatedAttributes = (transaction, parent, left, right, negatedAttrib
     left = right
     right = right.right
   }
-  for (let [key, val] of negatedAttributes) {
+  for (const [key, val] of negatedAttributes) {
     left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentFormat(key, val))
     left.integrate(transaction)
   }
@@ -214,7 +213,7 @@ const minimizeAttributeChanges = (left, right, currentAttributes, attributes) =>
 const insertAttributes = (transaction, parent, left, right, currentAttributes, attributes) => {
   const negatedAttributes = new Map()
   // insert format-start items
-  for (let key in attributes) {
+  for (const key in attributes) {
     const val = attributes[key]
     const currentVal = currentAttributes.get(key) || null
     if (!equalAttrs(currentVal, val)) {
@@ -241,7 +240,7 @@ const insertAttributes = (transaction, parent, left, right, currentAttributes, a
  * @function
  **/
 const insertText = (transaction, parent, left, right, currentAttributes, text, attributes) => {
-  for (let [key] of currentAttributes) {
+  for (const [key] of currentAttributes) {
     if (attributes[key] === undefined) {
       attributes[key] = null
     }
@@ -281,7 +280,7 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
   while (length > 0 && right !== null) {
     if (!right.deleted) {
       switch (right.content.constructor) {
-        case ContentFormat:
+        case ContentFormat: {
           const { key, value } = /** @type {ContentFormat} */ (right.content)
           const attr = attributes[key]
           if (attr !== undefined) {
@@ -294,6 +293,7 @@ const formatText = (transaction, parent, left, right, currentAttributes, length,
           }
           updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
           break
+        }
         case ContentEmbed:
         case ContentString:
           if (length < right.length) {
@@ -405,6 +405,7 @@ export class YTextEvent extends YEvent {
      */
     this._delta = null
   }
+
   /**
    * Compute the changes in the delta format.
    * A {@link https://quilljs.com/docs/delta/|Quill Delta}) that represents the changes on the document.
@@ -429,7 +430,10 @@ export class YTextEvent extends YEvent {
         /**
          * @type {Object<string,any>}
          */
-        let attributes = {} // counts added or removed new attributes for retain
+        const attributes = {} // counts added or removed new attributes for retain
+        /**
+         * @type {string|object}
+         */
         let insert = ''
         let retain = 0
         let deleteLen = 0
@@ -448,7 +452,7 @@ export class YTextEvent extends YEvent {
                 op = { insert }
                 if (currentAttributes.size > 0) {
                   op.attributes = {}
-                  for (let [key, value] of currentAttributes) {
+                  for (const [key, value] of currentAttributes) {
                     if (value !== null) {
                       op.attributes[key] = value
                     }
@@ -460,7 +464,7 @@ export class YTextEvent extends YEvent {
                 op = { retain }
                 if (Object.keys(attributes).length > 0) {
                   op.attributes = {}
-                  for (let key in attributes) {
+                  for (const key in attributes) {
                     op.attributes[key] = attributes[key]
                   }
                 }
@@ -518,7 +522,7 @@ export class YTextEvent extends YEvent {
                 retain += item.length
               }
               break
-            case ContentFormat:
+            case ContentFormat: {
               const { key, value } = /** @type {ContentFormat} */ (item.content)
               if (this.adds(item)) {
                 if (!this.deletes(item)) {
@@ -570,12 +574,13 @@ export class YTextEvent extends YEvent {
                 updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (item.content))
               }
               break
+            }
           }
           item = item.right
         }
         addOp()
         while (delta.length > 0) {
-          let lastOp = delta[delta.length - 1]
+          const lastOp = delta[delta.length - 1]
           if (lastOp.retain !== undefined && lastOp.attributes === undefined) {
             // retain delta's if they don't assign attributes
             delta.pop()
@@ -745,7 +750,7 @@ export class YText extends AbstractType {
          */
         const attributes = {}
         let addAttributes = false
-        for (let [key, value] of currentAttributes) {
+        for (const [key, value] of currentAttributes) {
           addAttributes = true
           attributes[key] = value
         }
@@ -772,7 +777,7 @@ export class YText extends AbstractType {
       while (n !== null) {
         if (isVisible(n, snapshot) || (prevSnapshot !== undefined && isVisible(n, prevSnapshot))) {
           switch (n.content.constructor) {
-            case ContentString:
+            case ContentString: {
               const cur = currentAttributes.get('ychange')
               if (snapshot !== undefined && !isVisible(n, snapshot)) {
                 if (cur === undefined || cur.user !== n.id.client || cur.state !== 'removed') {
@@ -790,6 +795,7 @@ export class YText extends AbstractType {
               }
               str += /** @type {ContentString} */ (n.content).str
               break
+            }
             case ContentEmbed:
               packStr()
               ops.push({
@@ -831,6 +837,7 @@ export class YText extends AbstractType {
         const { left, right, currentAttributes } = findPosition(transaction, this, index)
         if (!attributes) {
           attributes = {}
+          // @ts-ignore
           currentAttributes.forEach((v, k) => { attributes[k] = v })
         }
         insertText(transaction, this, left, right, currentAttributes, text, attributes)
@@ -902,7 +909,7 @@ export class YText extends AbstractType {
     const y = this.doc
     if (y !== null) {
       transact(y, transaction => {
-        let { left, right, currentAttributes } = findPosition(transaction, this, index)
+        const { left, right, currentAttributes } = findPosition(transaction, this, index)
         if (right === null) {
           return
         }

src/types/YXmlElement.js

@@ -74,7 +74,7 @@ export class YXmlElement extends YXmlFragment {
     const attrs = this.getAttributes()
     const stringBuilder = []
     const keys = []
-    for (let key in attrs) {
+    for (const key in attrs) {
       keys.push(key)
     }
     keys.sort()
@@ -140,7 +140,7 @@ export class YXmlElement extends YXmlFragment {
    * Returns all attribute name/value pairs in a JSON Object.
    *
    * @param {Snapshot} [snapshot]
-   * @return {Object} A JSON Object that describes the attributes.
+   * @return {Object<string, any>} A JSON Object that describes the attributes.
    *
    * @public
    */
@@ -165,8 +165,8 @@ export class YXmlElement extends YXmlFragment {
    */
   toDOM (_document = document, hooks = {}, binding) {
     const dom = _document.createElement(this.nodeName)
-    let attrs = this.getAttributes()
+    const attrs = this.getAttributes()
-    for (let key in attrs) {
+    for (const key in attrs) {
       dom.setAttribute(key, attrs[key])
     }
     typeListForEach(this, yxml => {

src/types/YXmlFragment.js

@@ -68,6 +68,7 @@ export class YXmlTreeWalker {
   [Symbol.iterator] () {
     return this
   }
+
   /**
    * Get the next node.
    *
@@ -130,6 +131,7 @@ export class YXmlFragment extends AbstractType {
      */
     this._prelimContent = []
   }
+
   /**
    * Integrate this type into the Yjs instance.
    *
@@ -143,7 +145,7 @@ export class YXmlFragment extends AbstractType {
    */
   _integrate (y, item) {
     super._integrate(y, item)
-    this.insert(0, /** @type {Array} */ (this._prelimContent))
+    this.insert(0, /** @type {Array<any>} */ (this._prelimContent))
     this._prelimContent = null
   }
 
@@ -307,6 +309,7 @@ export class YXmlFragment extends AbstractType {
       this._prelimContent.splice(index, length)
     }
   }
+
   /**
    * Transforms this YArray to a JavaScript Array.
    *
@@ -315,6 +318,7 @@ export class YXmlFragment extends AbstractType {
   toArray () {
     return typeListToArray(this)
   }
+
   /**
    * Transform the properties of this type to binary and write it to an
    * BinaryEncoder.

src/types/YXmlText.js

@@ -12,6 +12,7 @@ export class YXmlText extends YText {
   _copy () {
     return new YXmlText()
   }
+
   /**
    * Creates a Dom Element that mirrors this YXmlText.
    *
@@ -39,9 +40,9 @@ export class YXmlText extends YText {
     // @ts-ignore
     return this.toDelta().map(delta => {
       const nestedNodes = []
-      for (let nodeName in delta.attributes) {
+      for (const nodeName in delta.attributes) {
         const attrs = []
-        for (let key in delta.attributes[nodeName]) {
+        for (const key in delta.attributes[nodeName]) {
           attrs.push({ key, value: delta.attributes[nodeName][key] })
         }
         // sort attributes to get a unique order

src/utils/Doc.js

@@ -46,6 +46,7 @@ export class Doc extends Observable {
      */
     this._transactionCleanups = []
   }
+
   /**
    * Changes that happen inside of a transaction are bundled. This means that
    * the observer fires _after_ the transaction is finished and that all changes
@@ -60,6 +61,7 @@ export class Doc extends Observable {
   transact (f, origin = null) {
     transact(this, f, origin)
   }
+
   /**
    * Define a shared data type.
    *
@@ -118,6 +120,7 @@ export class Doc extends Observable {
     }
     return type
   }
+
   /**
    * @template T
    * @param {string} name
@@ -129,6 +132,7 @@ export class Doc extends Observable {
     // @ts-ignore
     return this.get(name, YArray)
   }
+
   /**
    * @param {string} name
    * @return {YText}
@@ -139,6 +143,7 @@ export class Doc extends Observable {
     // @ts-ignore
     return this.get(name, YText)
   }
+
   /**
    * @param {string} name
    * @return {YMap<any>}
@@ -149,6 +154,7 @@ export class Doc extends Observable {
     // @ts-ignore
     return this.get(name, YMap)
   }
+
   /**
    * @param {string} name
    * @return {YXmlFragment}
@@ -159,6 +165,7 @@ export class Doc extends Observable {
     // @ts-ignore
     return this.get(name, YXmlFragment)
   }
+
   /**
    * Emit `destroy` event and unregister all event handlers.
    *
@@ -168,6 +175,7 @@ export class Doc extends Observable {
     this.emit('destroyed', [true])
     super.destroy()
   }
+
   /**
    * @param {string} eventName
    * @param {function} f
@@ -175,6 +183,7 @@ export class Doc extends Observable {
   on (eventName, f) {
     super.on(eventName, f)
   }
+
   /**
    * @param {string} eventName
    * @param {function} f

src/utils/ID.js

@@ -81,7 +81,7 @@ export const readID = decoder =>
  */
 export const findRootTypeKey = type => {
   // @ts-ignore _y must be defined, otherwise unexpected case
-  for (let [key, value] of type.doc.share) {
+  for (const [key, value] of type.doc.share) {
     if (value === type) {
       return key
     }

src/utils/PermanentUserData.js

@@ -67,6 +67,7 @@ export class PermanentUserData {
     // add intial data
     users.forEach(initUser)
   }
+
   /**
    * @param {Doc} doc
    * @param {number} clientid
@@ -116,6 +117,7 @@ export class PermanentUserData {
       })
     })
   }
+
   /**
    * @param {number} clientid
    * @return {any}
@@ -123,6 +125,7 @@ export class PermanentUserData {
   getUserByClientId (clientid) {
     return this.clients.get(clientid) || null
   }
+
   /**
    * @param {ID} id
    * @return {string | null}

src/utils/RelativePosition.js

@@ -63,7 +63,7 @@ export class RelativePosition {
 }
 
 /**
- * @param {Object} json
+ * @param {any} json
  * @return {RelativePosition}
  *
  * @function

src/utils/StructStore.js

@@ -185,7 +185,7 @@ export const getItem = (store, id) => find(store, id)
  */
 export const findIndexCleanStart = (transaction, structs, clock) => {
   const index = findIndexSS(structs, clock)
-  let struct = structs[index]
+  const struct = structs[index]
   if (struct.id.clock < clock && struct instanceof Item) {
     structs.splice(index + 1, 0, splitItem(transaction, struct, clock - struct.id.clock))
     return index + 1

src/utils/YEvent.js

@@ -181,7 +181,7 @@ export class YEvent {
       })
       this._changes = changes
     }
-    return changes
+    return /** @type {any} */ (changes)
   }
 }
 

tests/testHelper.js

@@ -12,6 +12,7 @@ import * as prng from 'lib0/prng.js'
 import * as encoding from 'lib0/encoding.js'
 import * as decoding from 'lib0/decoding.js'
 import * as syncProtocol from 'y-protocols/sync.js'
+import * as object from 'lib0/object.js'
 export * from '../src/internals.js'
 
 /**
@@ -55,6 +56,7 @@ export class TestYInstance extends Doc {
     })
     this.connect()
   }
+
   /**
    * Disconnect from TestConnector.
    */
@@ -62,6 +64,7 @@ export class TestYInstance extends Doc {
     this.receiving = new Map()
     this.tc.onlineConns.delete(this)
   }
+
   /**
    * Append yourself to the list of known Y instances in testconnector.
    * Also initiate sync with all clients.
@@ -83,6 +86,7 @@ export class TestYInstance extends Doc {
       })
     }
   }
+
   /**
    * Receive a message from another client. This message is only appended to the list of receiving messages.
    * TestConnector decides when this client actually reads this message.
@@ -124,6 +128,7 @@ export class TestConnector {
      */
     this.prng = gen
   }
+
   /**
    * Create a new Y instance and add it to the list of connections
    * @param {number} clientID
@@ -131,6 +136,7 @@ export class TestConnector {
   createY (clientID) {
     return new TestYInstance(this, clientID)
   }
+
   /**
    * Choose random connection and flush a random message from a random sender.
    *
@@ -162,6 +168,7 @@ export class TestConnector {
     }
     return false
   }
+
   /**
    * @return {boolean} True iff this function actually flushed something
    */
@@ -172,16 +179,20 @@ export class TestConnector {
     }
     return didSomething
   }
+
   reconnectAll () {
     this.allConns.forEach(conn => conn.connect())
   }
+
   disconnectAll () {
     this.allConns.forEach(conn => conn.disconnect())
   }
+
   syncAll () {
     this.reconnectAll()
     this.flushAllMessages()
   }
+
   /**
    * @return {boolean} Whether it was possible to disconnect a randon connection.
    */
@@ -192,6 +203,7 @@ export class TestConnector {
     prng.oneOf(this.prng, Array.from(this.onlineConns)).disconnect()
     return true
   }
+
   /**
    * @return {boolean} Whether it was possible to reconnect a random connection.
    */
@@ -270,12 +282,12 @@ export const compare = users => {
   // Test Map iterator
   const ymapkeys = Array.from(users[0].getMap('map').keys())
   t.assert(ymapkeys.length === Object.keys(userMapValues[0]).length)
-  ymapkeys.forEach(key => t.assert(userMapValues[0].hasOwnProperty(key)))
+  ymapkeys.forEach(key => t.assert(object.hasProperty(userMapValues[0], key)))
   /**
    * @type {Object<string,any>}
    */
   const mapRes = {}
-  for (let [k, v] of users[0].getMap('map')) {
+  for (const [k, v] of users[0].getMap('map')) {
     mapRes[k] = v instanceof Y.AbstractType ? v.toJSON() : v
   }
   t.compare(userMapValues[0], mapRes)

tests/undo-redo.tests.js

@@ -69,11 +69,11 @@ export const testUndoMap = tc => {
   const subType = new Y.Map()
   map0.set('a', subType)
   subType.set('x', 42)
-  t.compare(map0.toJSON(), /** @type {any} */ ({ 'a': { x: 42 } }))
+  t.compare(map0.toJSON(), /** @type {any} */ ({ a: { x: 42 } }))
   undoManager.undo()
   t.assert(map0.get('a') === 1)
   undoManager.redo()
-  t.compare(map0.toJSON(), /** @type {any} */ ({ 'a': { x: 42 } }))
+  t.compare(map0.toJSON(), /** @type {any} */ ({ a: { x: 42 } }))
   testConnector.syncAll()
   // if content is overwritten by another user, undo operations should be skipped
   map1.set('a', 44)

tests/y-array.tests.js

@@ -227,7 +227,7 @@ export const testInsertAndDeleteEventsForTypes2 = tc => {
   /**
    * @type {Array<Object<string,any>>}
    */
-  let events = []
+  const events = []
   array0.observe(e => {
     events.push(e)
   })
@@ -318,7 +318,7 @@ export const testIteratingArrayContainingTypes = tc => {
     arr.push([map])
   }
   let cnt = 0
-  for (let item of arr) {
+  for (const item of arr) {
     t.assert(item.get('value') === cnt++, 'value is correct')
   }
   y.destroy()

tests/y-map.tests.js

@@ -66,7 +66,7 @@ export const testGetAndSetOfMapProperty = tc => {
 
   testConnector.flushAllMessages()
 
-  for (let user of users) {
+  for (const user of users) {
     const u = user.getMap('map')
     t.compare(u.get('stuff'), 'stuffy')
     t.assert(u.get('undefined') === undefined, 'undefined')
@@ -108,7 +108,7 @@ export const testGetAndSetOfMapPropertySyncs = tc => {
   map0.set('stuff', 'stuffy')
   t.compare(map0.get('stuff'), 'stuffy')
   testConnector.flushAllMessages()
-  for (let user of users) {
+  for (const user of users) {
     var u = user.getMap('map')
     t.compare(u.get('stuff'), 'stuffy')
   }
@@ -123,7 +123,7 @@ export const testGetAndSetOfMapPropertyWithConflict = tc => {
   map0.set('stuff', 'c0')
   map1.set('stuff', 'c1')
   testConnector.flushAllMessages()
-  for (let user of users) {
+  for (const user of users) {
     var u = user.getMap('map')
     t.compare(u.get('stuff'), 'c1')
   }
@@ -139,7 +139,7 @@ export const testGetAndSetAndDeleteOfMapProperty = tc => {
   map1.set('stuff', 'c1')
   map1.delete('stuff')
   testConnector.flushAllMessages()
-  for (let user of users) {
+  for (const user of users) {
     var u = user.getMap('map')
     t.assert(u.get('stuff') === undefined)
   }
@@ -156,7 +156,7 @@ export const testGetAndSetOfMapPropertyWithThreeConflicts = tc => {
   map1.set('stuff', 'c2')
   map2.set('stuff', 'c3')
   testConnector.flushAllMessages()
-  for (let user of users) {
+  for (const user of users) {
     var u = user.getMap('map')
     t.compare(u.get('stuff'), 'c3')
   }
@@ -179,7 +179,7 @@ export const testGetAndSetAndDeleteOfMapPropertyWithThreeConflicts = tc => {
   map3.set('stuff', 'c3')
   map3.delete('stuff')
   testConnector.flushAllMessages()
-  for (let user of users) {
+  for (const user of users) {
     var u = user.getMap('map')
     t.assert(u.get('stuff') === undefined)
   }
@@ -430,12 +430,12 @@ export const testYmapEventHasCorrectValueWhenSettingAPrimitiveFromOtherUser = tc
  */
 const mapTransactions = [
   function set (user, gen) {
-    let key = prng.oneOf(gen, ['one', 'two'])
+    const key = prng.oneOf(gen, ['one', 'two'])
     var value = prng.utf16String(gen)
     user.getMap('map').set(key, value)
   },
   function setType (user, gen) {
-    let key = prng.oneOf(gen, ['one', 'two'])
+    const key = prng.oneOf(gen, ['one', 'two'])
     var type = prng.oneOf(gen, [new Y.Array(), new Y.Map()])
     user.getMap('map').set(key, type)
     if (type instanceof Y.Array) {
@@ -445,7 +445,7 @@ const mapTransactions = [
     }
   },
   function _delete (user, gen) {
-    let key = prng.oneOf(gen, ['one', 'two'])
+    const key = prng.oneOf(gen, ['one', 'two'])
     user.getMap('map').delete(key)
   }
 ]

tests/y-text.tests.js

@@ -154,7 +154,7 @@ export const testSnapshotDeleteAfter = tc => {
  * @param {t.TestCase} tc
  */
 export const testToJson = tc => {
-  const {text0 } = init(tc, { users: 1 })
+  const { text0 } = init(tc, { users: 1 })
   text0.insert(0, 'abc', { bold: true })
   t.assert(text0.toJSON() === 'abc', 'toJSON returns the unformatted text')
 }

tests/y-xml.tests.js

@@ -60,13 +60,13 @@ export const testEvents = tc => {
  */
 export const testTreewalker = tc => {
   const { users, xml0 } = init(tc, { users: 3 })
-  let paragraph1 = new Y.XmlElement('p')
+  const paragraph1 = new Y.XmlElement('p')
-  let paragraph2 = new Y.XmlElement('p')
+  const paragraph2 = new Y.XmlElement('p')
-  let text1 = new Y.XmlText('init')
+  const text1 = new Y.XmlText('init')
-  let text2 = new Y.XmlText('text')
+  const text2 = new Y.XmlText('text')
   paragraph1.insert(0, [text1, text2])
   xml0.insert(0, [paragraph1, paragraph2, new Y.XmlElement('img')])
-  let allParagraphs = xml0.querySelectorAll('p')
+  const allParagraphs = xml0.querySelectorAll('p')
   t.assert(allParagraphs.length === 2, 'found exactly two paragraphs')
   t.assert(allParagraphs[0] === paragraph1, 'querySelectorAll found paragraph1')
   t.assert(allParagraphs[1] === paragraph2, 'querySelectorAll found paragraph2')