Fix watcher handling on unsaved objects (#39186).

Patch by Holger Just.


git-svn-id: https://svn.redmine.org/redmine/trunk@22349 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/plugins/acts_as_watchable/lib/acts_as_watchable.rb

@@ -11,6 +11,7 @@ module Redmine
       module ClassMethods
         def acts_as_watchable(options = {})
           return if self.included_modules.include?(Redmine::Acts::Watchable::InstanceMethods)
+
           class_eval do
             has_many :watchers, :as => :watchable, :dependent => :delete_all
             has_many :watcher_users, :through => :watchers, :source => :user, :validate => false
@@ -44,17 +45,26 @@ module Redmine
 
         # Adds user as a watcher
         def add_watcher(user)
-          # Rails does not reset the has_many :through association
-          watcher_users.reset
-          self.watchers << Watcher.new(:user => user)
+          if persisted?
+            # Rails does not reset the has_many :through association
+            watcher_users.reset
+            self.watchers << Watcher.new(:user => user)
+          else
+            self.watcher_users << user
+          end
         end
 
         # Removes user from the watchers list
         def remove_watcher(user)
           return nil unless user && (user.is_a?(User) || user.is_a?(Group))
-          # Rails does not reset the has_many :through association
-          watcher_users.reset
-          watchers.where(:user_id => user.id).delete_all
+
+          if persisted?
+            # Rails does not reset the has_many :through association
+            watcher_users.reset
+            watchers.where(:user_id => user.id).delete_all
+          else
+            watcher_users.delete(user)
+          end
         end
 
         # Adds/removes watcher