Makes user unwatch what he can no longer view after its permissions have changed (#3589).

A rake task (redmine:watchers:prune) is also added to prune existing watchers.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@3167 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/watcher.rb

@@ -21,10 +21,45 @@ class Watcher < ActiveRecord::Base
   
   validates_presence_of :user
   validates_uniqueness_of :user_id, :scope => [:watchable_type, :watchable_id]
+
+  # Unwatch things that users are no longer allowed to view
+  def self.prune(options={})
+    if options.has_key?(:user)
+      prune_single_user(options[:user], options)
+    else
+      pruned = 0
+      User.find(:all, :conditions => "id IN (SELECT DISTINCT user_id FROM #{table_name})").each do |user|
+        pruned += prune_single_user(user, options)
+      end
+      pruned
+    end
+  end
   
   protected
   
   def validate
     errors.add :user_id, :invalid unless user.nil? || user.active?
   end
+  
+  private
+  
+  def self.prune_single_user(user, options={})
+    return unless user.is_a?(User)
+    pruned = 0
+    find(:all, :conditions => {:user_id => user.id}).each do |watcher|
+      next if watcher.watchable.nil?
+      
+      if options.has_key?(:project)
+        next unless watcher.watchable.respond_to?(:project) && watcher.watchable.project == options[:project]
+      end
+      
+      if watcher.watchable.respond_to?(:visible?)
+        unless watcher.watchable.visible?(user)
+          watcher.destroy
+          pruned += 1
+        end
+      end
+    end
+    pruned
+  end
 end