Got a whole bunch of `fails` in your ruby codebase?

gistfile1.rb

module FailClassInference

  def fail(*args)
    return super unless args.first.is_a?(String)
    super(infer_exception_class, *args)
  end

  def raise(*args)
    return super unless args.first.is_a?(String)
    super(infer_exception_class, *args)
  end

  def infer_exception_class
    klass = self.is_a?(Class) ? self : self.class
    expected_error_klass = "StringError"
    error_klass = if klass.const_defined?(expected_error_klass)
      klass.const_get(expected_error_klass)
    else
      klass.const_set(expected_error_klass, Class.new(RuntimeError))
    end
  end
end

Object.include(FailClassInference)