class ActiveRecord::FixtureSet::ModelMetadata

def column_names
  @column_names ||= @model_class ? @model_class.columns.map(&:name).to_set : Set.new
end

def column_type(column_name)
  @column_type ||= {}
  return @column_type[column_name] if @column_type.key?(column_name)
  @column_type[column_name] = @model_class && @model_class.type_for_attribute(column_name).type
end

def has_column?(column_name)
  column_names.include?(column_name)
end

def inheritance_column_name
  @inheritance_column_name ||= @model_class && @model_class.inheritance_column
end

def initialize(model_class)
  @model_class = model_class
end

def primary_key_name
  @primary_key_name ||= @model_class && @model_class.primary_key
end

def primary_key_type
  @primary_key_type ||= @model_class && column_type(@model_class.primary_key)
end

def timestamp_column_names
  @model_class.all_timestamp_attributes_in_model
end