lib/midpay/hash/indifferent_access.rb
module Midpay
module HashExtensions
module IndifferentAccess
def self.included(base)
base.class_eval do
alias_method :regular_writer, :[]=
alias_method :[]=, :indifferent_writer
%w(default update fetch delete key? values_at).each do |m|
alias_method "regular_#{m}", m
alias_method m, "indifferent_#{m}"
end
%w(include? member? has_key?).each do |key_alias|
alias_method key_alias, :indifferent_key?
end
end
end
def self.inject!(hash)
(class << hash; self; end).send :include, IndifferentAccess
hash.convert!
end
def self.inject(hash)
inject!(hash.dup)
end
def convert_key(key)
key.to_s
end
def convert!
keys.each do |k|
regular_writer convert_key(k), convert_value(self.regular_delete(k))
end
self
end
def convert_value(value)
if hash_lacking_indifference?(value)
IndifferentAccess.inject(value.dup)
elsif value.is_a?(::Array)
value.dup.replace(value.map { |e| convert_value(e) })
else
value
end
end
def indifferent_default(key = nil)
return self[convert_key(key)] if key?(key)
regular_default(key)
end
def indifferent_update(other_hash)
return regular_update(other_hash) if hash_with_indifference?(other_hash)
other_hash.each_pair do |k,v|
self[k] = v
end
end
def indifferent_writer(key, value); regular_writer convert_key(key), convert_value(value) end
def indifferent_fetch(key, *args); regular_fetch convert_key(key), *args end
def indifferent_delete(key); regular_delete convert_key(key) end
def indifferent_key?(key); regular_key? convert_key(key) end
def indifferent_values_at(*indices); indices.map{|i| self[i] } end
def indifferent_access?; true end
protected
def hash_lacking_indifference?(other)
other.is_a?(::Hash) &&
!(other.respond_to?(:indifferent_access?) &&
other.indifferent_access?)
end
def hash_with_indifference?(other)
other.is_a?(::Hash) &&
other.respond_to?(:indifferent_access?) &&
other.indifferent_access?
end
end
end
end