Invalid date handling

date_error_handling.rb

module DateErrorHandling
  extend ActiveSupport::Concern

  INVALID_DATE = Date.new(9999, 1, 1).freeze

  # This method can be used to safely parse a date input, otherwise a parse error
  # can cause a crash, rather than simply an error message. It should be used in
  # collaboration with model validation, and to do that you can use the `on_error`
  # param to specify what should be returned on error. If your field is required
  # (i.e., allow_blank: false) you can call this with `on_error: nil` and validation
  # will fail as this is nil. If this field is optional, you should then use
  # `on_error: INVALID_DATE` and then add a custom validation to your model which
  # makes sure this field is not INVALID_DATE (and if it is, forces it to be nil
  # after adding the error to the array so the field is reset for the user).
  def safe_parse_date(date, on_error:)
    return date unless date.is_a?(Hash)

    begin
      Date.new(date[1], date[2], date[3])
    rescue Date::Error
      on_error
    end
  end
end

model.rb

class YourModelCLass
  include DateErrorHandling
  
  attribute :date_of_hearing, :date
  validates :date_of_hearing, ...

  validate :invalid_date

  def date_of_hearing=(date)
    super(safe_parse_date(date, on_error: INVALID_DATE))
  end
  
  ...
end