Fix DOM nodes cleanup-on-reuse bug

src/dom/pool.js

@@ -7,30 +7,30 @@ export default class Pool {
   }
 
   store (el) {
-    if (!this._recyclingEnabled) {
+    if (!this._recyclingEnabled || el._collected || !el.nodeType || el.nodeType !== 1 /* Node.ELEMENT_NODE == 1 */) {
       return
     }
+    el._collected = true
 
     if (el && el.parentNode) {
       el.parentNode.removeChild(el)
     }
 
-    if (!el.nodeType || el.nodeType !== 1 /* Node.ELEMENT_NODE == 1 */) {
-      return
-    }
 
     let tagName = el.tagName.toLowerCase()
     if (!this.storage[tagName]) {
       this.storage[tagName] = []
     }
 
     // little cleanup
+    el.className = ''
     for (let i = 0; i < el.attributes.length; i++) {
       el.removeAttribute(el.attributes[i].name)
     }
 
     if (el.childNodes.length > 0) {
-      for (let i = 0; i < el.childNodes.length; i++) {
+      // Iterate backwards, because childNodes is live collection
+      for (let i = el.childNodes.length - 1; i >=0; i--) {
         this.store(el.childNodes[i])
       }
     }
@@ -45,7 +45,9 @@ export default class Pool {
   get (tagName) {
     tagName = tagName.toLowerCase()
     if (this._recyclingEnabled && this.storage[tagName] && this.storage[tagName].length > 0) {
-      return this.storage[tagName].pop()
+      let el = this.storage[tagName].pop()
+      delete el._collected
+      return el
     }
     return createNativeElement(tagName)
   }

test/dom/pool.js

@@ -16,6 +16,26 @@ test('storeDomNode', t => {
   t.end()
 })
 
+test('storeNestedNodes', t => {
+  let node = document.createElement('div')
+  for (let i = 0; i < 10; i++) {
+    node.appendChild(document.createElement('div'))
+  }
+  let pool = new Pool()
+  pool.enableRecycling(true)
+
+  pool.store(node)
+
+  let childNodesCount = 0;
+  while (pool._getStorageSizeFor('div') > 0) {
+    let storedNode = pool.get('div')
+    childNodesCount += storedNode.childNodes.length
+  }
+
+  t.equal(childNodesCount, 0, 'Stored nested nodes were flattened and do not have children')
+  t.end()
+})
+
 test('getNewDomNode', t => {
   let pool = new Pool()
   let newNode = pool.get('div')