after upgrade 1.5.1 -> 1.5.2. 'top level based search' results in http:500 when 'Documents' is included #408

app/models/dmsf_folder.rb

@@ -317,8 +317,48 @@ class DmsfFolder < ActiveRecord::Base
     folder_links.visible.count +
     file_links.visible.count +
     url_links.visible.count
-  end    
+  end 
+  
+  # To full fill searchable module expectations in Redmine <= 3.0
+  # TODO: Remove this function in the next release
+  def self.search(tokens, projects = nil, options = {})
+    tokens = [] << tokens unless tokens.is_a?(Array)
+    projects = [] << projects unless projects.nil? || projects.is_a?(Array)
 
+    find_options = {}
+    find_options[:order] = 'dmsf_folders.updated_at ' + (options[:before] ? 'DESC' : 'ASC')
+
+    limit_options = {}
+    limit_options[:limit] = options[:limit] if options[:limit]
+    if options[:offset]
+      limit_options[:conditions] = '(dmsf_folders.updated_at ' + (options[:before] ? '<' : '>') + "'#{connection.quoted_date(options[:offset])}')"
+    end
+
+    columns = options[:titles_only] ? ['dmsf_folders.title'] : ['dmsf_folders.title', 'dmsf_folders.description']
+
+    token_clauses = columns.collect {|column| "(LOWER(#{column}) LIKE ?)"}
+
+    sql = (['(' + token_clauses.join(' OR ') + ')'] * tokens.size).join(options[:all_words] ? ' AND ' : ' OR ')
+    find_options[:conditions] = [sql, * (tokens.collect {|w| "%#{w.downcase}%"} * token_clauses.size).sort]
+
+    project_conditions = []
+    project_conditions << (Project.allowed_to_condition(User.current, :view_dmsf_files))
+    project_conditions << "project_id IN (#{projects.collect(&:id).join(',')})" if projects
+
+    results = []
+    results_count = 0
+    
+    includes(:project).
+    where(project_conditions.join(' AND ')).scoping do
+      where(find_options[:conditions]).order(find_options[:order]).scoping do
+        results_count = count(:all)
+        results = find(:all, limit_options)
+      end
+    end
+
+    [results, results_count]
+  end
+  
   private
 
   def self.directory_subtree(tree, folder, level, current_folder)