From b829f2a3aa85b106800ed2be29168506a591b407 Mon Sep 17 00:00:00 2001
From: Steven Orvell <sorvell@google.com>
Date: Thu, 12 Nov 2015 15:09:48 -0800
Subject: [PATCH] Fixes #2692. Ensures that custom-style properties are applied
 async but before next render so that all properties are defined before any
 are consumed by custom-styles. Also refines dom-module's early upgrade code
 so that it does not affect other elements (corrects for example,
 custom-styles upgrading before expected).

---
 src/lib/custom-style.html               |  6 +++-
 src/lib/dom-module.html                 | 18 +++++++---
 src/lib/render-status.html              | 44 +++++++++++++++++--------
 test/runner.html                        |  1 +
 test/unit/custom-style-late-import.html | 19 +++++++++++
 test/unit/custom-style-late.html        | 42 +++++++++++++++++++++++
 test/unit/custom-style.html             | 17 ++++++----
 7 files changed, 121 insertions(+), 26 deletions(-)
 create mode 100644 test/unit/custom-style-late-import.html
 create mode 100644 test/unit/custom-style-late.html

diff --git a/src/lib/custom-style.html b/src/lib/custom-style.html
index 4c78e526d9..ff791d650b 100644
--- a/src/lib/custom-style.html
+++ b/src/lib/custom-style.html
@@ -142,7 +142,11 @@
         styleUtil.forEachStyleRule(styleUtil.rulesForStyle(e), function(rule) {
           styleTransformer.documentRule(rule);
         });
-        this._applyCustomProperties(e);
+        // Allow all custom-styles defined in this turn to register
+        // before applying any properties. This helps ensure that all properties 
+        // are defined before any are consumed.
+        Polymer.RenderStatus.beforeNextRender(this, 
+          this._applyCustomProperties, [e]);
       }
     },
 
diff --git a/src/lib/dom-module.html b/src/lib/dom-module.html
index 36903984f2..4420bca61f 100644
--- a/src/lib/dom-module.html
+++ b/src/lib/dom-module.html
@@ -72,8 +72,8 @@
         if (!m) {
           // If polyfilling, a script can run before a dom-module element
           // is upgraded. We force the containing document to upgrade
-          // and try again to workaround this polyfill limitation.
-          forceDocumentUpgrade();
+          // dom-modules and try again to workaround this polyfill limitation.
+          forceDomModulesUpgrade();
           m = findModule(id);
         }
         if (m && selector) {
@@ -97,12 +97,20 @@
   var cePolyfill = window.CustomElements && !CustomElements.useNative;
   document.registerElement('dom-module', DomModule);
 
-  function forceDocumentUpgrade() {
+  function forceDomModulesUpgrade() {
     if (cePolyfill) {
       var script = document._currentScript || document.currentScript;
       var doc = script && script.ownerDocument || document;
-      if (doc) {
-        CustomElements.upgradeAll(doc);
+      // find all dom-modules
+      var modules = doc.querySelectorAll('dom-module');
+      // minimize work by going backwards and stopping if we find an 
+      // upgraded module.
+      for (var i= modules.length-1, m; (i >=0) && (m=modules[i]); i--) {
+        if (m.__upgraded__) {
+          return;
+        } else {
+          CustomElements.upgrade(m);
+        }
       }
     }
   }
diff --git a/src/lib/render-status.html b/src/lib/render-status.html
index eb687cf377..493c76dd74 100644
--- a/src/lib/render-status.html
+++ b/src/lib/render-status.html
@@ -50,33 +50,51 @@
     },
 
     _afterNextRenderQueue: [],
+    _beforeNextRenderQueue: [],
 
     _waitingNextRender: false,
 
     afterNextRender: function(element, fn, args) {
+      this._watchNextRender();
+      this._afterNextRenderQueue.push([element, fn, args]);
+    },
+
+    beforeNextRender: function(element, fn, args) {
+      this._watchNextRender();
+      this._beforeNextRenderQueue.push([element, fn, args]);
+    },
+
+    _watchNextRender: function() {
       if (!this._waitingNextRender) {
         this._waitingNextRender = true;
-        this.whenReady(this._flushAfterNextRender);
+        var fn = function() {
+          Polymer.RenderStatus._flushNextRender();
+        }
+        if (!this._ready) {
+          this.whenReady(fn);
+        } else {
+          requestAnimationFrame(fn);
+        }
       }
-      this._afterNextRenderQueue.push([element, fn, args]);
     },
 
-    _flushAfterNextRender: function() {
-      // we want to defer flush until just after the next paint.
-      requestAnimationFrame(function() {
-        setTimeout(Polymer.RenderStatus.__flushAfterNextRender);
+    _flushNextRender: function() {
+      this._waitingNextRender = false;
+      this._flushRenderCallbacks(this._beforeNextRenderQueue);
+      this._beforeNextRenderQueue = [];
+      var self = this;
+      // we want to defer after render until just after the paint.
+      setTimeout(function() {
+        self._flushRenderCallbacks(self._afterNextRenderQueue);
+        self._afterNextRenderQueue = [];
       });
     },
 
-    __flushAfterNextRender: function() {
-      // called without context so force here.
-      var self = Polymer.RenderStatus;
-      self._waitingNextRender = false;
-      for (var i=0, h; i < self._afterNextRenderQueue.length; i++) {
-        h = self._afterNextRenderQueue[i];
+    _flushRenderCallbacks: function(callbacks) {
+      for (var i=0, h; i < callbacks.length; i++) {
+        h = callbacks[i];
         h[1].apply(h[0], h[2] || Polymer.nar);
       };
-      self._afterNextRenderQueue = [];
     }
   };
 
diff --git a/test/runner.html b/test/runner.html
index b2431e9acf..f92b70f780 100644
--- a/test/runner.html
+++ b/test/runner.html
@@ -61,6 +61,7 @@
       // 'unit/styling-cross-scope-apply.html?dom=shadow',
       'unit/styling-cross-scope-unknown-host.html',
       'unit/custom-style.html',
+      'unit/custom-style-late.html',
       'unit/dynamic-import.html',
       'unit/templatizer.html',
       'unit/dom-repeat.html',
diff --git a/test/unit/custom-style-late-import.html b/test/unit/custom-style-late-import.html
new file mode 100644
index 0000000000..fa6f62beeb
--- /dev/null
+++ b/test/unit/custom-style-late-import.html
@@ -0,0 +1,19 @@
+<script>
+  Polymer({
+    is: 'x-input',
+    extends : 'input'
+  });
+</script>
+<style is="custom-style">
+  input[is=x-input] {
+    border : 4px solid red;
+    @apply (--cs-blue);
+  }
+</style>
+<style is="custom-style">
+  :root {
+    --cs-blue: {
+      border : 8px solid blue;
+    };
+  }
+</style>
\ No newline at end of file
diff --git a/test/unit/custom-style-late.html b/test/unit/custom-style-late.html
new file mode 100644
index 0000000000..92a28df75b
--- /dev/null
+++ b/test/unit/custom-style-late.html
@@ -0,0 +1,42 @@
+<!doctype html>
+<!--
+@license
+Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+-->
+<html>
+<head>
+  <meta charset="utf-8">
+  <script src="../../../webcomponentsjs/webcomponents-lite.js"></script>
+  <script src="../../../web-component-tester/browser.js"></script>
+  <link rel="import" href="../../polymer.html">
+  <link rel="import" href="custom-style-late-import.html">
+  
+</head>
+<body>
+  <input id="input" is="x-input">
+
+  <script>
+
+    suite('custom-style late property definition', function() {
+
+      test('late defined properties applied to custom-style', function() {
+        assertComputed(input, '8px');
+      });
+      
+    });
+
+    function assertComputed(element, value, property, pseudo) {
+      var computed = getComputedStyle(element, pseudo);
+      property = property || 'border-top-width';
+      assert.equal(computed[property], value, 'computed style incorrect for ' + property);
+    }
+
+  </script>
+
+</body>
+</html>
diff --git a/test/unit/custom-style.html b/test/unit/custom-style.html
index 7c7b702e00..65630f2ac2 100644
--- a/test/unit/custom-style.html
+++ b/test/unit/custom-style.html
@@ -365,11 +365,11 @@
         var ds = document.createElement('style', 'custom-style');
         ds.textContent = ':root { --dynamic: 11px solid orange; }';
         document.head.appendChild(ds);
-        setTimeout(function() {
-          Polymer.updateStyles();
+        Polymer.updateStyles();
+        Polymer.RenderStatus.afterNextRender(null, function() {
           assertComputed(dynamic, '11px');
           done();
-        }, 0);
+        });
       });
 
       test('custom-styles apply normal and property values to elements and cannot be late bound via inheritance', function() {
@@ -409,7 +409,7 @@
         document.body.removeChild(style);
       });
 
-      test('imperative custom style with include', function() {
+      test('imperative custom style with include', function(done) {
         var style = document.createElement('style', 'custom-style');
         style.include = 'shared-style2';
         var d = document.createElement('div');
@@ -417,9 +417,12 @@
         document.body.appendChild(d);
         document.body.appendChild(style);
         CustomElements.takeRecords();
-        assertComputed(d, '16px');
-        document.body.removeChild(d);
-        document.body.removeChild(style);
+        Polymer.RenderStatus.afterNextRender(null, function() {
+          assertComputed(d, '16px');
+          document.body.removeChild(d);
+          document.body.removeChild(style);
+          done();
+        });
       });
 
       test('imperative custom style with non-existent include', function() {