Redmine

This happens when issues are bulk copied and the tracker and/or the project is changed. In these cases the custom field values just get deleted.

Here's a patch that will keep applicable custom field values instead of deleting them all:

diff --git a/app/models/issue.rb b/app/models/issue.rb
index 53d7823..9c71538 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -228,7 +228,7 @@ class Issue < ActiveRecord::Base
   def tracker_id=(tid)
     self.tracker = nil
     result = write_attribute(:tracker_id, tid)
-    @custom_field_values = nil
+    recalculate_custom_field_values!
     result
   end

@@ -257,7 +257,7 @@ class Issue < ActiveRecord::Base
       if parent && parent.project_id != project_id
         self.parent_issue_id = nil
       end
-      @custom_field_values = nil
+      recalculate_custom_field_values!
     end
   end

diff --git a/vendor/plugins/acts_as_customizable/lib/acts_as_customizable.rb b/vendor/plugins/acts_as_customizable/lib/acts_as_customizable.rb
index cfee2c5..d1db757 100644
--- a/vendor/plugins/acts_as_customizable/lib/acts_as_customizable.rb
+++ b/vendor/plugins/acts_as_customizable/lib/acts_as_customizable.rb
@@ -153,6 +153,16 @@ module Redmine
           @custom_field_values_changed = true
         end

+        # Recalculate custom_field_values based on current available_custom_fields.
+        # We need to make sure no extraneous custom_field_values are saved,
+        # #custom_field_values= will only save values for custom fields available
+        # to this object.
+        def recalculate_custom_field_values!
+          cfv_hash = custom_field_values.inject({}) {|h,cfv| h[cfv.custom_field.id] = cfv.value; h}
+          reset_custom_values!
+          self.custom_field_values = cfv_hash
+        end
+
         module ClassMethods
         end
       end