From d9f3dda973af5d97017cbace8b3770f0db3238ad Mon Sep 17 00:00:00 2001
From: Nazar Mokrynskyi <nazar@mokrynskyi.com>
Date: Sun, 6 Sep 2015 01:01:31 +0200
Subject: [PATCH 1/2] Eliminate the need to write `:host ::content` instead of
 just `::content`, while keeping the same processing under the hood

---
 src/lib/style-transformer.html      | 5 ++---
 test/unit/polymer-dom-elements.html | 6 +++---
 2 files changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/lib/style-transformer.html b/src/lib/style-transformer.html
index 1a072f76..a8832f7a 100644
--- a/src/lib/style-transformer.html
+++ b/src/lib/style-transformer.html
@@ -30,9 +30,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
      * :host(...) -> scopeName...
 
-     * ::content -> ' ' NOTE: requires use of scoping selector and selectors
-       cannot otherwise be scoped:
-       e.g. :host ::content > .bar -> x-foo > .bar
+     * ::content -> ' '
 
      * ::shadow, /deep/: processed similar to ::content
 
@@ -161,6 +159,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         var stop = false;
         var hostContext = false;
         var self = this;
+        selector = selector.replace(/^(::content)/, ':host $1');
         selector = selector.replace(SIMPLE_SELECTOR_SEP, function(m, c, s) {
           if (!stop) {
             var info = self._transformCompoundSelector(s, c, scope, hostScope);
diff --git a/test/unit/polymer-dom-elements.html b/test/unit/polymer-dom-elements.html
index d4afa8b2..53956048 100644
--- a/test/unit/polymer-dom-elements.html
+++ b/test/unit/polymer-dom-elements.html
@@ -200,7 +200,7 @@
       box-sizing: border-box;
     }
 
-    :host ::content .add3 {
+    ::content .add3 {
       box-sizing: border-box;
       height: 20px;
       background: #333;
@@ -240,7 +240,7 @@
       padding: 4px;
     }
 
-    :host ::content .add2 {
+    ::content .add2 {
       box-sizing: border-box;
       height: 20px;
       background: gray;
@@ -281,7 +281,7 @@
       padding: 4px;
     }
 
-    :host ::content .add1 {
+    ::content .add1 {
       box-sizing: border-box;
       height: 20px;
       background: lightgray;

From c6c28f51970c8be164823356ce7211d3ad5ff829 Mon Sep 17 00:00:00 2001
From: Nazar Mokrynskyi <nazar@mokrynskyi.com>
Date: Mon, 2 Nov 2015 04:32:39 +0100
Subject: [PATCH 2/2] Using constant rather than plain `:host` and `::content`,
 also create regexp object only once

---
 src/lib/style-transformer.html | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/lib/style-transformer.html b/src/lib/style-transformer.html
index a8832f7a..419c38d6 100644
--- a/src/lib/style-transformer.html
+++ b/src/lib/style-transformer.html
@@ -159,7 +159,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
         var stop = false;
         var hostContext = false;
         var self = this;
-        selector = selector.replace(/^(::content)/, ':host $1');
+        selector = selector.replace(CONTENT_START, HOST + ' $1');
         selector = selector.replace(SIMPLE_SELECTOR_SEP, function(m, c, s) {
           if (!stop) {
             var info = self._transformCompoundSelector(s, c, scope, hostScope);
@@ -255,7 +255,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     // NOTE: this supports 1 nested () pair for things like
     // :host(:not([selected]), more general support requires
     // parsing which seems like overkill
-    var HOST_PAREN = /(\:host)(?:\(((?:\([^)(]*\)|[^)(]*)+?)\))/g;
+    var HOST_PAREN = /(:host)(?:\(((?:\([^)(]*\)|[^)(]*)+?)\))/g;
     var HOST_CONTEXT = ':host-context';
     var HOST_CONTEXT_PAREN = /(.*)(?::host-context)(?:\(((?:\([^)(]*\)|[^)(]*)+?)\))(.*)/;
     var CONTENT = '::content';
@@ -265,6 +265,7 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
     var CSS_ATTR_SUFFIX = ']';
     var PSEUDO_PREFIX = ':';
     var CLASS = 'class';
+    var CONTENT_START = new RegExp('^(' + CONTENT + ')');
 
     // exports
     return api;