Learnings

NoMethodError: undefined method `learned_on` on `new` learning page

Context: The new.html.erb view tried to access @learning.learned_on to set the default value for the date field (value: @learning.learned_on || Date.today), causing NoMethodError.
Resolution: I changed the date_field value in the view to just value: Date.today. The @learning instance created by LearningsController#new (Learning.new) is unsaved and doesn't have attributes populated from database defaults until saved.
Learning: I learned to be mindful of when database defaults are applied (on save) versus needing to set defaults explicitly in the controller (Model.new(attr: default)) or view (value: default) for new object instances presented in forms.