From 5076ee0b88fe8d8d6498692e2ce0c4ba7294006c Mon Sep 17 00:00:00 2001
From: Kevin Schaaf <kschaaf@google.com>
Date: Wed, 18 Nov 2015 15:07:35 -0800
Subject: [PATCH 1/2] Avoid throwing with invalid keys/paths. Fixes #3018.

---
 src/lib/collection.html       | 36 ++++++++++++++++++-----------------
 src/standard/notify-path.html |  4 +++-
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/src/lib/collection.html b/src/lib/collection.html
index 71cd691336..997b3a5f3a 100644
--- a/src/lib/collection.html
+++ b/src/lib/collection.html
@@ -50,9 +50,10 @@
     },
 
     removeKey: function(key) {
-      key = this._parseKey(key);
-      this._removeFromMap(this.store[key]);
-      delete this.store[key];
+      if (key = this._parseKey(key)) {
+        this._removeFromMap(this.store[key]);
+        delete this.store[key];
+      }
     },
 
     _removeFromMap: function(item) {
@@ -88,29 +89,30 @@
     },
 
     _parseKey: function(key) {
-      if (key[0] == '#') {
+      if (key && key[0] == '#') {
         return key.slice(1);
       }
-      throw new Error('unexpected key ' + key);
     },
 
     setItem: function(key, item) {
-      key = this._parseKey(key);
-      var old = this.store[key];
-      if (old) {
-        this._removeFromMap(old);
-      }
-      if (item && typeof item == 'object') {
-        this.omap.set(item, key);
-      } else {
-        this.pmap[item] = key;
+      if (key = this._parseKey(key)) {
+        var old = this.store[key];
+        if (old) {
+          this._removeFromMap(old);
+        }
+        if (item && typeof item == 'object') {
+          this.omap.set(item, key);
+        } else {
+          this.pmap[item] = key;
+        }
+        this.store[key] = item;
       }
-      this.store[key] = item;
     },
 
     getItem: function(key) {
-      key = this._parseKey(key);
-      return this.store[key];
+      if (key = this._parseKey(key)) {
+        return this.store[key];
+      }
     },
 
     getItems: function() {
diff --git a/src/standard/notify-path.html b/src/standard/notify-path.html
index 927f8403d4..328a6cbba9 100644
--- a/src/standard/notify-path.html
+++ b/src/standard/notify-path.html
@@ -85,7 +85,9 @@
         var info = {};
         this._get(path, this, info);
         // Notify change to key-based path
-        this._notifyPath(info.path, value, fromAbove);
+        if (info.path) {
+          this._notifyPath(info.path, value, fromAbove);
+        }
       },
 
       // Note: this implemetation only accepts key-based array paths

From 108b7f98e49cad55bcb76a9de6711a975adda746 Mon Sep 17 00:00:00 2001
From: Steven Orvell <sorvell@google.com>
Date: Thu, 19 Nov 2015 12:07:13 -0800
Subject: [PATCH 2/2] Add a couple of tests.

---
 test/unit/notify-path.html | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/test/unit/notify-path.html b/test/unit/notify-path.html
index 11d42f22ca..7cc82c414d 100644
--- a/test/unit/notify-path.html
+++ b/test/unit/notify-path.html
@@ -856,6 +856,18 @@
     assert.equal(el.get('nested.again.again.wayOverThere'), 99);
   });
 
+  test('notifyPath calls observer', function() {
+    el.a = {b: {c: true}};
+    sinon.spy(el, 'aChanged');
+    el.notifyPath('a.b.c', el.a.b.c);
+    assert.isTrue(el.aChanged.calledOnce);
+    assert.equal(el.get('a.b.c'), true);
+  });
+
+  test('notifyPath a non-extistant does nothing', function() {
+    el.notifyPath('does.not.exist', true);
+  });
+
   test('get array', function() {
     el.arrayChanged = function() {};
     el.array = [1, 2, 3];