Wiki Redirects and Page Renaming

Added the ability to rename existing pages.
[[!redirects Some Page Name]] redirects Wikilinks [[Some Page Name]] to
  the current page (assuming "Some Page Name" does not exist).
  Real pages trump redirects (though this may change, depending on 
  user feedback).

app/controllers/file_controller.rb

@@ -129,7 +129,7 @@ class FileController < ApplicationController
             next
           else
             logger.info "Page '#{page_name}' already exists. Adding a new revision to it."
-            wiki.revise_page(@web.address, page_name, page_content, Time.now, @author, PageRenderer.new)
+            wiki.revise_page(@web.address, page_name, page_name, page_content, Time.now, @author, PageRenderer.new)
           end
         else
           wiki.write_page(@web.address, page_name, page_content, Time.now, @author, PageRenderer.new)

app/controllers/revision_sweeper.rb

@@ -22,8 +22,9 @@ class RevisionSweeper < ActionController::Caching::Sweeper
   
   def expire_caches(page)
     expire_cached_summary_pages(page.web)
-    pages_to_expire = ([page.name] + WikiReference.pages_that_reference(page.web, page.name) +  
-        WikiReference.pages_that_include(page.web, page.name)).uniq
+    pages_to_expire = ([page.name] + WikiReference.pages_that_reference(page.web, page.name)   
+        + WikiReference.pages_redirected_to(page.web, page.name) 
+        + WikiReference.pages_that_include(page.web, page.name)).uniq
     pages_to_expire.each { |page_name| expire_cached_page(page.web, page_name) }
   end
 

app/controllers/web_sweeper.rb

@@ -12,7 +12,7 @@ class WebSweeper < ActionController::Caching::Sweeper
       web.pages.each { |page| expire_cached_page(web, page.name) }
       expire_cached_summary_pages(web)
     elsif record.is_a?(WikiFile)
-      record.web.pages_that_link_to(record.file_name).each do |page|
+      record.web.pages_that_link_to_file(record.file_name).each do |page|
         expire_cached_page(record.web, page)
       end
       expire_cached_summary_pages(record.web)

app/controllers/wiki_controller.rb

@@ -268,9 +268,13 @@ class WikiController < ApplicationController
         raise Instiki::ValidationError.new('Your content was not valid utf-8.')
       end
       if @page
-        wiki.revise_page(@web_name, @page_name, the_content, Time.now, 
+        new_name = params['new_name'] || @page_name
+        raise Instiki::ValidationError.new('Your new title was not valid utf-8.') unless new_name.is_utf8?
+        raise Instiki::ValidationError.new('A page named "' + new_name.escapeHTML + '" already exists.') if @page_name != new_name && @web.has_page?(new_name)
+        wiki.revise_page(@web_name, @page_name, new_name, the_content, Time.now, 
             Author.new(author_name, remote_ip), PageRenderer.new)
         @page.unlock
+        @page_name = new_name
       else
         wiki.write_page(@web_name, @page_name, the_content, Time.now, 
             Author.new(author_name, remote_ip), PageRenderer.new)