fix: emoji markup in code block was corrupted (#57)

When the gem nokogiri >= 1.11.x, any node selected by css selector
will not be managed once its parent node is assigned to new inner
html, this will introduce problems that changing node properties
isn't working.

Author: jeffreytse

lib/jekyll-spaceship/processors/emoji-processor.rb

@@ -44,13 +44,24 @@ def emoji_filter(content, selector)
       # page's layout field of front matter is nil or unavailable
       return content if body.nil?
 
+      # Count for restoration
+      escaped_count = 0
+
       # filter nodes (pre, code)
-      nodes = body.css(selector)
-      nodes.each do |node|
+      body.css(selector).each do |node|
+        count = escaped_count
+
         # handle emoji markup
-        node.inner_html = node.inner_html.gsub(
-          /:([\w\d+-]+?):/, '\:\1\:'
-        )
+        inner_html = node.inner_html.gsub(
+          /(?<!\\):([\w\d+-]+?)(?<!\\):/
+        ) do |match|
+          escaped_count += 1
+          "\\:#{match[1..-2]}\\:"
+        end
+
+        if escaped_count > count
+          node.inner_html = inner_html
+        end
       end
 
       # parse the emoji
@@ -73,8 +84,10 @@ def emoji_filter(content, selector)
 
       body.inner_html = content
 
+      return doc.to_html if escaped_count.zero?
+
       # restore nodes (pre, code)
-      nodes.each do |node|
+      body.css(selector).each do |node|
         # handle emoji markup
         node.inner_html = node.inner_html.gsub(
           /\\:([\w\d+-]+?)\\:/, ':\1:'