require 'strscan'
module Psych
###
# Scan scalars for built in types
class ScalarScanner
# Taken from http://yaml.org/type/timestamp.html
TIME = /^-?\d{4}-\d{1,2}-\d{1,2}(?:[Tt]|\s+)\d{1,2}:\d\d:\d\d(?:\.\d*)?(?:\s*(?:Z|[-+]\d{1,2}:?(?:\d\d)?))?$/
# Taken from http://yaml.org/type/float.html
FLOAT = /^(?:[-+]?([0-9][0-9_,]*)?\.[0-9]*([eE][-+][0-9]+)?(?# base 10)
|[-+]?[0-9][0-9_,]*(:[0-5]?[0-9])+\.[0-9_]*(?# base 60)
|[-+]?\.(inf|Inf|INF)(?# infinity)
|\.(nan|NaN|NAN)(?# not a number))$/x
# Taken from http://yaml.org/type/int.html
INTEGER = /^(?:[-+]?0b[0-1_]+ (?# base 2)
|[-+]?0[0-7_]+ (?# base 8)
|[-+]?(?:0|[1-9][0-9_]*) (?# base 10)
|[-+]?0x[0-9a-fA-F_]+ (?# base 16))$/x
attr_reader :class_loader
# Create a new scanner
def initialize class_loader
@string_cache = {}
@symbol_cache = {}
@class_loader = class_loader
end
# Tokenize +string+ returning the Ruby object
def tokenize string
return nil if string.empty?
return string if @string_cache.key?(string)
return @symbol_cache[string] if @symbol_cache.key?(string)
case string
# Check for a String type, being careful not to get caught by hash keys, hex values, and
# special floats (e.g., -.inf).
when /^[^\d\.:-]?[A-Za-z_\s!@#\$%\^&\*\(\)\{\}\<\>\|\/\\~;=]+/, /\n/
if string.length > 5
@string_cache[string] = true
return string
end
case string
when /^[^ytonf~]/i
@string_cache[string] = true
string
when '~', /^null$/i
nil
when /^(yes|true|on)$/i
true
when /^(no|false|off)$/i
false
else
@string_cache[string] = true
string
end
when TIME
begin
parse_time string
rescue ArgumentError
string
end
when /^\d{4}-(?:1[012]|0\d|\d)-(?:[12]\d|3[01]|0\d|\d)$/
require 'date'
begin
class_loader.date.strptime(string, '%Y-%m-%d')
rescue ArgumentError
string
end
when /^\.inf$/i
Float::INFINITY
when /^-\.inf$/i
-Float::INFINITY
when /^\.nan$/i
Float::NAN
when /^:./
if string =~ /^:(["'])(.*)\1/
@symbol_cache[string] = class_loader.symbolize($2.sub(/^:/, ''))
else
@symbol_cache[string] = class_loader.symbolize(string.sub(/^:/, ''))
end
when /^[-+]?[0-9][0-9_]*(:[0-5]?[0-9])+$/
i = 0
string.split(':').each_with_index do |n,e|
i += (n.to_i * 60 ** (e - 2).abs)
end
i
when /^[-+]?[0-9][0-9_]*(:[0-5]?[0-9])+\.[0-9_]*$/
i = 0
string.split(':').each_with_index do |n,e|
i += (n.to_f * 60 ** (e - 2).abs)
end
i
when FLOAT
if string =~ /\A[-+]?\.\Z/
@string_cache[string] = true
string
else
Float(string.gsub(/[,_]|\.$/, ''))
end
else
int = parse_int string.gsub(/[,_]/, '')
return int if int
@string_cache[string] = true
string
end
end
###
# Parse and return an int from +string+
def parse_int string
return unless INTEGER === string
Integer(string)
end
###
# Parse and return a Time from +string+
def parse_time string
klass = class_loader.load 'Time'
date, time = *(string.split(/[ tT]/, 2))
(yy, m, dd) = date.match(/^(-?\d{4})-(\d{1,2})-(\d{1,2})/).captures.map { |x| x.to_i }
md = time.match(/(\d+:\d+:\d+)(?:\.(\d*))?\s*(Z|[-+]\d+(:\d\d)?)?/)
(hh, mm, ss) = md[1].split(':').map { |x| x.to_i }
us = (md[2] ? Rational("0.#{md[2]}") : 0) * 1000000
time = klass.utc(yy, m, dd, hh, mm, ss, us)
return time if 'Z' == md[3]
return klass.at(time.to_i, us) unless md[3]
tz = md[3].match(/^([+\-]?\d{1,2})\:?(\d{1,2})?$/)[1..-1].compact.map { |digit| Integer(digit, 10) }
offset = tz.first * 3600
if offset < 0
offset -= ((tz[1] || 0) * 60)
else
offset += ((tz[1] || 0) * 60)
end
klass.at((time - offset).to_i, us)
end
end
end
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