Proposed change to build_association

build_association.rb

# Returns a new, unsaved instance of the associated class. +options+ will
# be passed to the class's constructor.
def build_association(*options, &block)
    if options.first.is_a?(Hash) && (subclass_name = options.first.with_indifferent_access[klass.inheritance_column]).present?
        begin
            subclass = klass.module_eval { compute_type(subclass_name) }
            raise NameError unless (subclass == klass || subclass.ancestors.include?(klass))
            subclass.new(*options, &block)
        rescue NameError
            raise ActiveRecord::SubclassNotFound.new("Invalid single-table inheritance type: #{subclass_name} is not a subclass of #{klass.name}")
        end
    else
        klass.new(*options, &block)
    end
end

All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy. All work and no play makes Jack a dull boy.

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