Handle embedded images in repository docs

Rules

@@ -33,6 +33,14 @@ route '/assets/*' do
   end
 end
 
+# TODO(ts): Remove these hacks once the nanoc4 upgrade is done.
+compile '*/images/*' do
+end
+
+route '*/images/*' do
+  item.identifier.chop + '.' + item[:extension]
+end
+
 route '/README/' do
     '/README.md'
 end

lib/filters/normalize_links.rb

@@ -9,9 +9,8 @@ class NormalizeLinks < ::Nanoc::Filter
 
   def run(content, config = {})
     doc = Nokogiri::HTML(content)
-    links = doc.xpath('//a')
 
-    links.each do |link|
+    doc.xpath('//a').each do |link|
       link['href'] =
         case
         when link['href'].start_with?(DOMAIN)
@@ -26,6 +25,11 @@ class NormalizeLinks < ::Nanoc::Filter
         end
     end
 
+    doc.xpath('//img').each do |img|
+      next if img['src'].start_with?('/') || img['src'].start_with?('http')
+      img['src'] = File.join("../", img['src'])
+    end
+
     doc.to_s
   end