rails--rails/activesupport/lib/active_support/json/backends/yaml.rb

91 lines
2.9 KiB
Ruby

require 'active_support/core_ext/string/starts_ends_with'
module ActiveSupport
module JSON
module Backends
module Yaml
ParseError = ::StandardError
extend self
# Parses a JSON string or IO and converts it into an object
def decode(json)
if json.respond_to?(:read)
json = json.read
end
YAML.load(convert_json_to_yaml(json))
rescue ArgumentError => e
raise ParseError, "Invalid JSON string"
end
protected
# Ensure that ":" and "," are always followed by a space
def convert_json_to_yaml(json) #:nodoc:
require 'strscan' unless defined? ::StringScanner
scanner, quoting, marks, pos, times = ::StringScanner.new(json), false, [], nil, []
while scanner.scan_until(/(\\['"]|['":,\\]|\\.)/)
case char = scanner[1]
when '"', "'"
if !quoting
quoting = char
pos = scanner.pos
elsif quoting == char
if json[pos..scanner.pos-2] =~ DATE_REGEX
# found a date, track the exact positions of the quotes so we can
# overwrite them with spaces later.
times << pos << scanner.pos
end
quoting = false
end
when ":",","
marks << scanner.pos - 1 unless quoting
when "\\"
scanner.skip(/\\/)
end
end
if marks.empty?
json.gsub(/\\([\\\/]|u[[:xdigit:]]{4})/) do
ustr = $1
if ustr.start_with?('u')
[ustr[1..-1].to_i(16)].pack("U")
elsif ustr == '\\'
'\\\\'
else
ustr
end
end
else
left_pos = [-1].push(*marks)
right_pos = marks << scanner.pos + scanner.rest_size
output = []
left_pos.each_with_index do |left, i|
scanner.pos = left.succ
chunk = scanner.peek(right_pos[i] - scanner.pos + 1)
# overwrite the quotes found around the dates with spaces
while times.size > 0 && times[0] <= right_pos[i]
chunk[times.shift - scanner.pos - 1] = ' '
end
chunk.gsub!(/\\([\\\/]|u[[:xdigit:]]{4})/) do
ustr = $1
if ustr.start_with?('u')
[ustr[1..-1].to_i(16)].pack("U")
elsif ustr == '\\'
'\\\\'
else
ustr
end
end
output << chunk
end
output = output * " "
output.gsub!(/\\\//, '/')
output
end
end
end
end
end
end