ruby/lib/csv/fields_converter.rb

79 строки
2.1 KiB
Ruby

# frozen_string_literal: true
class CSV
class FieldsConverter
include Enumerable
def initialize(options={})
@converters = []
@nil_value = options[:nil_value]
@empty_value = options[:empty_value]
@empty_value_is_empty_string = (@empty_value == "")
@accept_nil = options[:accept_nil]
@builtin_converters = options[:builtin_converters]
@need_static_convert = need_static_convert?
end
def add_converter(name=nil, &converter)
if name.nil? # custom converter
@converters << converter
else # named converter
combo = @builtin_converters[name]
case combo
when Array # combo converter
combo.each do |sub_name|
add_converter(sub_name)
end
else # individual named converter
@converters << combo
end
end
end
def each(&block)
@converters.each(&block)
end
def empty?
@converters.empty?
end
def convert(fields, headers, lineno)
return fields unless need_convert?
fields.collect.with_index do |field, index|
if field.nil?
field = @nil_value
elsif field.empty?
field = @empty_value unless @empty_value_is_empty_string
end
@converters.each do |converter|
break if field.nil? and @accept_nil
if converter.arity == 1 # straight field converter
field = converter[field]
else # FieldInfo converter
if headers
header = headers[index]
else
header = nil
end
field = converter[field, FieldInfo.new(index, lineno, header)]
end
break unless field.is_a?(String) # short-circuit pipeline for speed
end
field # final state of each field, converted or original
end
end
private
def need_static_convert?
not (@nil_value.nil? and @empty_value_is_empty_string)
end
def need_convert?
@need_static_convert or
(not @converters.empty?)
end
end
end