Very unsafe. Spoilage is your least worry, as both beans and rice can be associated with spore forming bacteria that cause food borne illness. "Warn" setting is very likely less that 140 degrees, the temperature at which food should be held for short periods of time to be safe.
In addition, My guess is you have had to add water somewhere along that two week period which would lower the temp for quite a while and every time you spoon out some beans, you are potentially contaminating the rest with the utensil.
Even our resident food safety naysayers probably wouldn't feel comfortable with two weeks on warm.