1 files changed, 27 insertions, 9 deletions

diff --git a/railties/guides/rails_guides/generator.rb b/railties/guides/rails_guides/generator.rb
index 18fdb81810..8e69af5bde 100644
--- a/railties/guides/rails_guides/generator.rb
+++ b/railties/guides/rails_guides/generator.rb
@@ -109,8 +109,8 @@ module RailsGuides
     end
 
     def textile(body)
-      # If the issue with nontextile is fixed just remove the wrapper.
-      with_workaround_for_nontextile(body) do |body|
+      # If the issue with notextile is fixed just remove the wrapper.
+      with_workaround_for_notextile(body) do |body|
         t = RedCloth.new(body)
         t.hard_breaks = false
         t.to_html(:notestuff, :plusplus, :code, :tip)
@@ -120,33 +120,51 @@ module RailsGuides
     # For some reason the notextile tag does not always turn off textile. See
     # LH ticket of the security guide (#7). As a temporary workaround we deal
     # with code blocks by hand.
-    def with_workaround_for_nontextile(body)
+    def with_workaround_for_notextile(body)
       code_blocks = []
       body.gsub!(%r{<(yaml|shell|ruby|erb|html|sql|plain)>(.*?)</\1>}m) do |m|
         es = ERB::Util.h($2)
         css_class = ['erb', 'shell'].include?($1) ? 'html' : $1
         code_blocks << %{<div class="code_container"><code class="#{css_class}">#{es}</code></div>}
-        "dirty_workaround_for_nontextile_#{code_blocks.size - 1}"
+        "\ndirty_workaround_for_notextile_#{code_blocks.size - 1}\n"
       end
       
       body = yield body
       
-      body.gsub(%r{<p>dirty_workaround_for_nontextile_(\d+)</p>}) do |_|
+      body.gsub(%r{<p>dirty_workaround_for_notextile_(\d+)</p>}) do |_|
         code_blocks[$1.to_i]
       end
     end
 
     def warn_about_broken_links(html)
+      anchors = extract_anchors(html)
+      check_fragment_identifiers(html, anchors)
+    end
+    
+    def extract_anchors(html)
       # Textile generates headers with IDs computed from titles.
-      anchors  = Set.new(html.scan(/<h\d\s+id="([^"]+)/).flatten)
+      anchors = Set.new
+      html.scan(/<h\d\s+id="([^"]+)/).flatten.each do |anchor|
+        if anchors.member?(anchor)
+          puts "*** DUPLICATE HEADER ID: #{anchor}, please consider rewording"
+        else
+          anchors << anchor
+        end
+      end
+
       # Also, footnotes are rendered as paragraphs this way.
       anchors += Set.new(html.scan(/<p\s+class="footnote"\s+id="([^"]+)/).flatten)
-      
-      # Check fragment identifiers.
+      return anchors
+    end
+    
+    def check_fragment_identifiers(html, anchors)
       html.scan(/<a\s+href="#([^"]+)/).flatten.each do |fragment_identifier|
         next if fragment_identifier == 'mainCol' # in layout, jumps to some DIV
         unless anchors.member?(fragment_identifier)
-          puts "BROKEN LINK: ##{fragment_identifier}"
+          guess = anchors.min { |a, b|
+            Levenshtein.distance(fragment_identifier, a) <=> Levenshtein.distance(fragment_identifier, b)
+          }
+          puts "*** BROKEN LINK: ##{fragment_identifier}, perhaps you meant ##{guess}."
         end
       end
     end