From 1b4a978162d8d67720418b64ab42ae54060e2701 Mon Sep 17 00:00:00 2001
From: Daniel Freedman <dfreedm@google.com>
Date: Tue, 21 Mar 2017 14:20:30 -0700
Subject: [PATCH] Remove support for lazy-upgrade inside dom-if and dom-repeat

This is very complicated to set up, and I'm not sure there are actually
any good use cases. If you can control when an element is stamped, you
really don't need to use disable-upgrade on it.
---
 lib/mixins/lazy-upgrade-mixin.html | 27 ---------------------------
 test/unit/lazy-upgrade.html        | 30 +++++++++++-------------------
 2 files changed, 11 insertions(+), 46 deletions(-)

diff --git a/lib/mixins/lazy-upgrade-mixin.html b/lib/mixins/lazy-upgrade-mixin.html
index c70a325b36..2bfebfd20a 100644
--- a/lib/mixins/lazy-upgrade-mixin.html
+++ b/lib/mixins/lazy-upgrade-mixin.html
@@ -58,10 +58,6 @@
         node.removeAttribute(LAZY_UPGRADE);
       }
 
-      function eventInCurrentScope(scope, event) {
-        return event.target === event.composedPath()[0];
-      }
-
       /** @polymerMixinClass */
       return class LazyUpgrade extends base {
         static get properties() {
@@ -84,8 +80,6 @@
         }
 
         ready() {
-          // check for dom-repeat and dom-if elements stamping lazy-upgrade nodes
-          this.addEventListener('dom-change', (ev) => { this.__lazyUpgradeFromDomChange(ev) });
           super.ready();
           this.__lazyUpgradeQueue = findCandidates(this.shadowRoot || this);
           this._lazyUpgrading = true;
@@ -108,27 +102,6 @@
             this._lazyUpgrading = false;
           }
         }
-
-        /**
-         * @private
-         */
-        __lazyUpgradeFromDomChange(ev) {
-          if (!eventInCurrentScope(this, ev)) {
-            return;
-          }
-          let root = ev.composedPath()[0].parentNode;
-          let candidates = findCandidates(root);
-          for (let i = 0; i < candidates.length; i++) {
-            let c = candidates[i];
-            if (this.__lazyUpgradeQueue.indexOf(c) === -1) {
-              this.__lazyUpgradeQueue.push(c);
-            }
-          }
-          if (candidates.length && !this._lazyUpgrading) {
-            this._lazyUpgrading = true;
-            this.__lazyUpgrade();
-          }
-        }
       }
     });
   })();
diff --git a/test/unit/lazy-upgrade.html b/test/unit/lazy-upgrade.html
index 1d8ca3017f..8359136f63 100644
--- a/test/unit/lazy-upgrade.html
+++ b/test/unit/lazy-upgrade.html
@@ -70,11 +70,15 @@
     <lazy-child id="two" disable-upgrade lazy-upgrade="1"></lazy-child>
     <lazy-child id="three"></lazy-child>
     <dom-if lazy-upgrade="1">
-      <lazy-child id="four" disable-upgrade lazy-upgrade></lazy-child>
+      <template>
+        <lazy-child id="four"></lazy-child>
+      </template>
     </dom-if>
     <lazy-child id="five" disable-upgrade></lazy-child>
     <dom-if lazy-upgrade>
-      <lazy-child id="six"></lazy-child>
+      <template>
+        <lazy-child id="six"></lazy-child>
+      </template>
     </dom-if>
   </template>
   <script>
@@ -107,12 +111,6 @@
   </dom-if>
   <lazy-child id="three" disable-upgrade></lazy-child>
   <lazy-child id="four" disable-upgrade lazy-upgrade></lazy-child>
-  <dom-if lazy-upgrade>
-    <template>
-      <lazy-child id="five" disable-upgrade></lazy-child>
-      <lazy-child id="six" disable-upgrade lazy-upgrade></lazy-child>
-    </template>
-  </dom-if>
 </template>
 
 <template id="critical">
@@ -132,13 +130,9 @@
 <dom-module id="no-upgrade-shadow">
   <template>
     <lazy-child id="one" disable-upgrade lazy-upgrade></lazy-child>
-    <dom-if if>
-      <template>
-        <lazy-child id="two" disable-upgrade lazy-upgrade></lazy-child>
-      </template>
-    </dom-if>
   </template>
 </dom-module>
+
 <script>
   addEventListener('WebComponentsReady', () => {
     customElements.define('no-upgrade-shadow', class extends Polymer.Element {
@@ -197,12 +191,10 @@
       el.appendChild(document.importNode(template.content, true));
       el.addEventListener('lazy-upgrade-finished', () => {
         let children = el.querySelectorAll('lazy-child');
-        assert.equal(children.length, 5);
+        assert.equal(children.length, 3);
         assertRendered(children[0], true);
         assertRendered(children[1], false);
         assertRendered(children[2], true);
-        assertRendered(children[3], false);
-        assertRendered(children[4], true);
         document.body.removeChild(el);
         done();
       });
@@ -235,10 +227,10 @@
         assert.equal(children.length, 6);
         let expected = [
           "three",
-          "six",
           "one",
-          "four",
-          "two"
+          "two",
+          "six",
+          "four"
         ];
         assert.deepEqual(el.upgradedChildren.map(n => n.id), expected);
         document.body.removeChild(el);