Add compatibility with gemoji v2

lib/html/pipeline/emoji_filter.rb

@@ -14,9 +14,6 @@ class Pipeline
     #   :asset_root (required) - base url to link to emoji sprite
     #   :asset_path (optional) - url path to link to emoji sprite. :file_name can be used as a placeholder for the sprite file name. If no asset_path is set "emoji/:file_name" is used.
     class EmojiFilter < Filter
-      # Build a regexp that matches all valid :emoji: names.
-      EmojiPattern = /:(#{Emoji.names.map { |name| Regexp.escape(name) }.join('|')}):/
-
       def call
         doc.search('text()').each do |node|
           content = node.to_html
@@ -43,7 +40,7 @@ def validate
       def emoji_image_filter(text)
         return text unless text.include?(':')
 
-        text.gsub EmojiPattern do |match|
+        text.gsub(emoji_pattern) do |match|
           name = $1
           "<img class='emoji' title=':#{name}:' alt=':#{name}:' src='#{emoji_url(name)}' height='20' width='20' align='absmiddle' />"
         end
@@ -63,9 +60,9 @@ def asset_root
       # Returns the context's asset_path or the default path if no context asset_path is given.
       def asset_path(name)
         if context[:asset_path]
-          context[:asset_path].gsub(":file_name", "#{::CGI.escape(name)}.png")
+          context[:asset_path].gsub(":file_name", emoji_filename(name))
         else
-          File.join("emoji", "#{::CGI.escape(name)}.png")
+          File.join("emoji", emoji_filename(name))
         end
       end
 
@@ -74,6 +71,35 @@ def asset_path(name)
       def emoji_url(name)
         File.join(asset_root, asset_path(name))
       end
+
+      # Build a regexp that matches all valid :emoji: names.
+      def self.emoji_pattern
+        @emoji_pattern ||= /:(#{emoji_names.map { |name| Regexp.escape(name) }.join('|')}):/
+      end
+
+      def emoji_pattern
+        self.class.emoji_pattern
+      end
+
+      # Detect gemoji v2 which has a new API
+      # https://github.com/jch/html-pipeline/pull/129
+      if Emoji.respond_to?(:all)
+        def self.emoji_names
+          Emoji.all.map(&:aliases).flatten.sort
+        end
+
+        def emoji_filename(name)
+          Emoji.find_by_alias(name).image_filename
+        end
+      else
+        def self.emoji_names
+          Emoji.names
+        end
+
+        def emoji_filename(name)
+          "#{::CGI.escape(name)}.png"
+        end
+      end
     end
   end
 end