require 'psych/scalar_scanner'
require 'psych/class_loader'
require 'psych/exception'
unless defined?(Regexp::NOENCODING)
Regexp::NOENCODING = 32
end
module Psych
module Visitors
###
# This class walks a YAML AST, converting each node to Ruby
class ToRuby < Psych::Visitors::Visitor
def self.create
class_loader = ClassLoader.new
scanner = ScalarScanner.new class_loader
new(scanner, class_loader)
end
attr_reader :class_loader
def initialize ss, class_loader
super()
@st = {}
@ss = ss
@domain_types = Psych.domain_types
@class_loader = class_loader
end
def accept target
result = super
return result if @domain_types.empty? || !target.tag
key = target.tag.sub(/^[!\/]*/, '').sub(/(,\d+)\//, '\1:')
key = "tag:#{key}" unless key =~ /^(tag:|x-private)/
if @domain_types.key? key
value, block = @domain_types[key]
return block.call value, result
end
result
end
def deserialize o
if klass = resolve_class(Psych.load_tags[o.tag])
instance = klass.allocate
if instance.respond_to?(:init_with)
coder = Psych::Coder.new(o.tag)
coder.scalar = o.value
instance.init_with coder
end
return instance
end
return o.value if o.quoted
return @ss.tokenize(o.value) unless o.tag
case o.tag
when '!binary', 'tag:yaml.org,2002:binary'
o.value.unpack('m').first
when /^!(?:str|ruby\/string)(?::(.*))?/, 'tag:yaml.org,2002:str'
klass = resolve_class($1)
if klass
klass.allocate.replace o.value
else
o.value
end
when '!ruby/object:BigDecimal'
require 'bigdecimal'
class_loader.big_decimal._load o.value
when "!ruby/object:DateTime"
class_loader.date_time
require 'date'
@ss.parse_time(o.value).to_datetime
when '!ruby/encoding'
::Encoding.find o.value
when "!ruby/object:Complex"
class_loader.complex
Complex(o.value)
when "!ruby/object:Rational"
class_loader.rational
Rational(o.value)
when "!ruby/class", "!ruby/module"
resolve_class o.value
when "tag:yaml.org,2002:float", "!float"
Float(@ss.tokenize(o.value))
when "!ruby/regexp"
klass = class_loader.regexp
o.value =~ /^\/(.*)\/([mixn]*)$/
source = $1
options = 0
lang = nil
($2 || '').split('').each do |option|
case option
when 'x' then options |= Regexp::EXTENDED
when 'i' then options |= Regexp::IGNORECASE
when 'm' then options |= Regexp::MULTILINE
when 'n' then options |= Regexp::NOENCODING
else lang = option
end
end
klass.new(*[source, options, lang].compact)
when "!ruby/range"
klass = class_loader.range
args = o.value.split(/([.]{2,3})/, 2).map { |s|
accept Nodes::Scalar.new(s)
}
args.push(args.delete_at(1) == '...')
klass.new(*args)
when /^!ruby\/sym(bol)?:?(.*)?$/
class_loader.symbolize o.value
else
@ss.tokenize o.value
end
end
private :deserialize
def visit_Psych_Nodes_Scalar o
register o, deserialize(o)
end
def visit_Psych_Nodes_Sequence o
if klass = resolve_class(Psych.load_tags[o.tag])
instance = klass.allocate
if instance.respond_to?(:init_with)
coder = Psych::Coder.new(o.tag)
coder.seq = o.children.map { |c| accept c }
instance.init_with coder
end
return instance
end
case o.tag
when nil
register_empty(o)
when '!omap', 'tag:yaml.org,2002:omap'
map = register(o, Psych::Omap.new)
o.children.each { |a|
map[accept(a.children.first)] = accept a.children.last
}
map
when /^!(?:seq|ruby\/array):(.*)$/
klass = resolve_class($1)
list = register(o, klass.allocate)
o.children.each { |c| list.push accept c }
list
else
register_empty(o)
end
end
def visit_Psych_Nodes_Mapping o
if Psych.load_tags[o.tag]
return revive(resolve_class(Psych.load_tags[o.tag]), o)
end
return revive_hash(register(o, {}), o) unless o.tag
case o.tag
when /^!ruby\/struct:?(.*)?$/
klass = resolve_class($1) if $1
if klass
s = register(o, klass.allocate)
members = {}
struct_members = s.members.map { |x| class_loader.symbolize x }
o.children.each_slice(2) do |k,v|
member = accept(k)
value = accept(v)
if struct_members.include?(class_loader.symbolize(member))
s.send("#{member}=", value)
else
members[member.to_s.sub(/^@/, '')] = value
end
end
init_with(s, members, o)
else
klass = class_loader.struct
members = o.children.map { |c| accept c }
h = Hash[*members]
klass.new(*h.map { |k,v|
class_loader.symbolize k
}).new(*h.map { |k,v| v })
end
when /^!ruby\/object:?(.*)?$/
name = $1 || 'Object'
if name == 'Complex'
class_loader.complex
h = Hash[*o.children.map { |c| accept c }]
register o, Complex(h['real'], h['image'])
elsif name == 'Rational'
class_loader.rational
h = Hash[*o.children.map { |c| accept c }]
register o, Rational(h['numerator'], h['denominator'])
else
obj = revive((resolve_class(name) || class_loader.object), o)
obj
end
when /^!(?:str|ruby\/string)(?::(.*))?/, 'tag:yaml.org,2002:str'
klass = resolve_class($1)
members = {}
string = nil
o.children.each_slice(2) do |k,v|
key = accept k
value = accept v
if key == 'str'
if klass
string = klass.allocate.replace value
else
string = value
end
register(o, string)
else
members[key] = value
end
end
init_with(string, members.map { |k,v| [k.to_s.sub(/^@/, ''),v] }, o)
when /^!ruby\/array:(.*)$/
klass = resolve_class($1)
list = register(o, klass.allocate)
members = Hash[o.children.map { |c| accept c }.each_slice(2).to_a]
list.replace members['internal']
members['ivars'].each do |ivar, v|
list.instance_variable_set ivar, v
end
list
when '!ruby/range'
klass = class_loader.range
h = Hash[*o.children.map { |c| accept c }]
register o, klass.new(h['begin'], h['end'], h['excl'])
when /^!ruby\/exception:?(.*)?$/
h = Hash[*o.children.map { |c| accept c }]
e = build_exception((resolve_class($1) || class_loader.exception),
h.delete('message'))
init_with(e, h, o)
when '!set', 'tag:yaml.org,2002:set'
set = class_loader.psych_set.new
@st[o.anchor] = set if o.anchor
o.children.each_slice(2) do |k,v|
set[accept(k)] = accept(v)
end
set
when /^!map:(.*)$/, /^!ruby\/hash:(.*)$/
revive_hash register(o, resolve_class($1).new), o
when '!omap', 'tag:yaml.org,2002:omap'
map = register(o, class_loader.psych_omap.new)
o.children.each_slice(2) do |l,r|
map[accept(l)] = accept r
end
map
else
revive_hash(register(o, {}), o)
end
end
def visit_Psych_Nodes_Document o
accept o.root
end
def visit_Psych_Nodes_Stream o
o.children.map { |c| accept c }
end
def visit_Psych_Nodes_Alias o
@st.fetch(o.anchor) { raise BadAlias, "Unknown alias: #{o.anchor}" }
end
private
def register node, object
@st[node.anchor] = object if node.anchor
object
end
def register_empty object
list = register(object, [])
object.children.each { |c| list.push accept c }
list
end
def revive_hash hash, o
o.children.each_slice(2) { |k,v|
key = accept(k)
val = accept(v)
if key == '<<'
case v
when Nodes::Alias
begin
hash.merge! val
rescue TypeError
hash[key] = val
end
when Nodes::Sequence
begin
h = {}
val.reverse_each do |value|
h.merge! value
end
hash.merge! h
rescue TypeError
hash[key] = val
end
else
hash[key] = val
end
else
hash[key] = val
end
}
hash
end
def merge_key hash, key, val
end
def revive klass, node
s = register(node, klass.allocate)
init_with(s, revive_hash({}, node), node)
end
def init_with o, h, node
c = Psych::Coder.new(node.tag)
c.map = h
if o.respond_to?(:init_with)
o.init_with c
elsif o.respond_to?(:yaml_initialize)
if $VERBOSE
warn "Implementing #{o.class}#yaml_initialize is deprecated, please implement \"init_with(coder)\""
end
o.yaml_initialize c.tag, c.map
else
h.each { |k,v| o.instance_variable_set(:"@#{k}", v) }
end
o
end
# Convert +klassname+ to a Class
def resolve_class klassname
class_loader.load klassname
end
end
class NoAliasRuby < ToRuby
def visit_Psych_Nodes_Alias o
raise BadAlias, "Unknown alias: #{o.anchor}"
end
end
end
end