From 4e1c81dc2944ce5943a1d91a035f260ab2583560 Mon Sep 17 00:00:00 2001
From: Kevin Schaaf <kschaaf@google.com>
Date: Fri, 28 Aug 2015 16:10:30 -0700
Subject: [PATCH] Add beforeRegister; ES6 class must set proto metadata here.
 Fixes #2382

---
 src/lib/base.html                 |  3 +-
 src/lib/dom-module.html           | 24 ++++++++-------
 test/unit/behaviors-elements.html | 49 +++++++++++++++++++++----------
 test/unit/behaviors.html          |  7 ++++-
 4 files changed, 55 insertions(+), 28 deletions(-)

diff --git a/src/lib/base.html b/src/lib/base.html
index 0fe7c19ed9..675bacb0d3 100644
--- a/src/lib/base.html
+++ b/src/lib/base.html
@@ -26,8 +26,9 @@
     registerCallback: function() {
       // TODO(sjmiles): perhaps this method should be called from polymer-bootstrap?
       this._desugarBehaviors(); // abstract
-      this._doBehavior('registered'); // abstract
+      this._doBehavior('beforeRegister'); // abstract
       this._registerFeatures();  // abstract
+      this._doBehavior('registered'); // abstract
     },
 
     createdCallback: function() {
diff --git a/src/lib/dom-module.html b/src/lib/dom-module.html
index ce8db00f36..0d532565b6 100644
--- a/src/lib/dom-module.html
+++ b/src/lib/dom-module.html
@@ -67,18 +67,20 @@
      * at the specified `id`.
      */
     import: function(id, selector) {
-      var m = findModule(id);
-      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();
-        m = findModule(id);
-      }
-      if (m && selector) {
-        m = m.querySelector(selector);
+      if (id) {
+        var m = findModule(id);
+        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();
+          m = findModule(id);
+        }
+        if (m && selector) {
+          m = m.querySelector(selector);
+        }
+        return m;
       }
-      return m;
     }
 
   });
diff --git a/test/unit/behaviors-elements.html b/test/unit/behaviors-elements.html
index fcfe49697e..3ceaba2ea1 100644
--- a/test/unit/behaviors-elements.html
+++ b/test/unit/behaviors-elements.html
@@ -219,26 +219,45 @@
 
 </dom-module>
 
-<dom-module id="registration-behaviors">
+<dom-module id="behavior-as-is">
 
-  <script>
+  <template><div id="content"></div></template>
 
-    Polymer.registerBehavior ={
-      registered: function() {
-        this.is = this.as;
-      }
-    };
+</dom-module>
 
-    Polymer({
+<script>
 
-      behaviors: [
-        Polymer.registerBehavior
-      ],
+  Polymer.registerBehavior ={
+    beforeRegister: function() {
+      this.is = this.as;
+      this.properties = {
+        prop: {
+          observer: 'propChanged1'
+        }
+      };
+      this.hostAttributes = {
+        attr: true
+      };
+      this.observers = [
+        'propChanged2(prop)'
+      ];
+    },
+    propChanged1: function() {
+      this.propChanged1Called = true;
+    },
+    propChanged2: function() {
+      this.propChanged2Called = true;
+    }
+  };
 
-      as: 'behavior-as-is'
+  Polymer({
 
-    });
+    behaviors: [
+      Polymer.registerBehavior
+    ],
 
-  </script>
+    as: 'behavior-as-is'
+
+  });
 
-</dom-module>
\ No newline at end of file
+</script>
\ No newline at end of file
diff --git a/test/unit/behaviors.html b/test/unit/behaviors.html
index 8702551a6d..d45b372283 100644
--- a/test/unit/behaviors.html
+++ b/test/unit/behaviors.html
@@ -52,9 +52,14 @@
     assert.equal(typeof el._setHasOptionsA, 'function');
   });
 
-  test('registered behavior', function() {
+  test('beforeRegister behavior', function() {
     var el = document.createElement('behavior-as-is');
     assert.equal(el.is, 'behavior-as-is');
+    assert.ok(el.$.content);
+    el.prop = 42;
+    assert.isTrue(el.propChanged1Called);
+    assert.isTrue(el.propChanged2Called);
+    assert.isTrue(el.hasAttribute('attr'));
   });
 
 });