require 'psych/tree_builder'
require 'psych/scalar_scanner'
require 'psych/class_loader'
module Psych
module Visitors
###
# YAMLTree builds a YAML ast given a Ruby object. For example:
#
# builder = Psych::Visitors::YAMLTree.new
# builder << { :foo => 'bar' }
# builder.tree # => #<Psych::Nodes::Stream .. }
#
class YAMLTree < Psych::Visitors::Visitor
class Registrar # :nodoc:
def initialize
@obj_to_id = {}
@obj_to_node = {}
@counter = 0
end
def register target, node
@obj_to_node[target.object_id] = node
end
def key? target
@obj_to_node.key? target.object_id
end
def id_for target
@obj_to_id[target.object_id] ||= (@counter += 1)
end
def node_for target
@obj_to_node[target.object_id]
end
end
attr_reader :started, :finished
alias :finished? :finished
alias :started? :started
def self.create options = {}, emitter = nil
emitter ||= TreeBuilder.new
class_loader = ClassLoader.new
ss = ScalarScanner.new class_loader
new(emitter, ss, options)
end
def self.new emitter = nil, ss = nil, options = nil
return super if emitter && ss && options
if $VERBOSE
warn "This API is deprecated, please pass an emitter, scalar scanner, and options or call #{self}.create() (#{caller.first})"
end
create emitter, ss
end
def initialize emitter, ss, options
super()
@started = false
@finished = false
@emitter = emitter
@st = Registrar.new
@ss = ss
@options = options
@coders = []
@dispatch_cache = Hash.new do |h,klass|
method = "visit_#{(klass.name || '').split('::').join('_')}"
method = respond_to?(method) ? method : h[klass.superclass]
raise(TypeError, "Can't dump #{target.class}") unless method
h[klass] = method
end
end
def start encoding = Nodes::Stream::UTF8
@emitter.start_stream(encoding).tap do
@started = true
end
end
def finish
@emitter.end_stream.tap do
@finished = true
end
end
def tree
finish unless finished?
@emitter.root
end
def push object
start unless started?
version = []
version = [1,1] if @options[:header]
case @options[:version]
when Array
version = @options[:version]
when String
version = @options[:version].split('.').map { |x| x.to_i }
else
version = [1,1]
end if @options.key? :version
@emitter.start_document version, [], false
accept object
@emitter.end_document !@emitter.streaming?
end
alias :<< :push
def accept target
# return any aliases we find
if @st.key? target
oid = @st.id_for target
node = @st.node_for target
anchor = oid.to_s
node.anchor = anchor
return @emitter.alias anchor
end
if target.respond_to?(:to_yaml)
begin
loc = target.method(:to_yaml).source_location.first
if loc !~ /(syck\/rubytypes.rb|psych\/core_ext.rb)/
unless target.respond_to?(:encode_with)
if $VERBOSE
warn "implementing to_yaml is deprecated, please implement \"encode_with\""
end
target.to_yaml(:nodump => true)
end
end
rescue
# public_method or source_location might be overridden,
# and it's OK to skip it since it's only to emit a warning
end
end
if target.respond_to?(:encode_with)
dump_coder target
else
send(@dispatch_cache[target.class], target)
end
end
def visit_Psych_Omap o
seq = @emitter.start_sequence(nil, '!omap', false, Nodes::Sequence::BLOCK)
register(o, seq)
o.each { |k,v| visit_Hash k => v }
@emitter.end_sequence
end
def visit_Encoding o
tag = "!ruby/encoding"
@emitter.scalar o.name, nil, tag, false, false, Nodes::Scalar::ANY
end
def visit_Object o
tag = Psych.dump_tags[o.class]
unless tag
klass = o.class == Object ? nil : o.class.name
tag = ['!ruby/object', klass].compact.join(':')
end
map = @emitter.start_mapping(nil, tag, false, Nodes::Mapping::BLOCK)
register(o, map)
dump_ivars o
@emitter.end_mapping
end
def visit_Struct o
tag = ['!ruby/struct', o.class.name].compact.join(':')
register o, @emitter.start_mapping(nil, tag, false, Nodes::Mapping::BLOCK)
o.members.each do |member|
@emitter.scalar member.to_s, nil, nil, true, false, Nodes::Scalar::ANY
accept o[member]
end
dump_ivars o
@emitter.end_mapping
end
def visit_Exception o
tag = ['!ruby/exception', o.class.name].join ':'
@emitter.start_mapping nil, tag, false, Nodes::Mapping::BLOCK
{
'message' => private_iv_get(o, 'mesg'),
'backtrace' => private_iv_get(o, 'backtrace'),
}.each do |k,v|
next unless v
@emitter.scalar k, nil, nil, true, false, Nodes::Scalar::ANY
accept v
end
dump_ivars o
@emitter.end_mapping
end
def visit_Regexp o
register o, @emitter.scalar(o.inspect, nil, '!ruby/regexp', false, false, Nodes::Scalar::ANY)
end
def visit_DateTime o
formatted = if o.offset.zero?
o.strftime("%Y-%m-%d %H:%M:%S.%9N Z".freeze)
else
o.strftime("%Y-%m-%d %H:%M:%S.%9N %:z".freeze)
end
tag = '!ruby/object:DateTime'
register o, @emitter.scalar(formatted, nil, tag, false, false, Nodes::Scalar::ANY)
end
def visit_Time o
formatted = format_time o
register o, @emitter.scalar(formatted, nil, nil, true, false, Nodes::Scalar::ANY)
end
def visit_Rational o
register o, @emitter.start_mapping(nil, '!ruby/object:Rational', false, Nodes::Mapping::BLOCK)
[
'denominator', o.denominator.to_s,
'numerator', o.numerator.to_s
].each do |m|
@emitter.scalar m, nil, nil, true, false, Nodes::Scalar::ANY
end
@emitter.end_mapping
end
def visit_Complex o
register o, @emitter.start_mapping(nil, '!ruby/object:Complex', false, Nodes::Mapping::BLOCK)
['real', o.real.to_s, 'image', o.imag.to_s].each do |m|
@emitter.scalar m, nil, nil, true, false, Nodes::Scalar::ANY
end
@emitter.end_mapping
end
def visit_Integer o
@emitter.scalar o.to_s, nil, nil, true, false, Nodes::Scalar::ANY
end
alias :visit_TrueClass :visit_Integer
alias :visit_FalseClass :visit_Integer
alias :visit_Date :visit_Integer
def visit_Float o
if o.nan?
@emitter.scalar '.nan', nil, nil, true, false, Nodes::Scalar::ANY
elsif o.infinite?
@emitter.scalar((o.infinite? > 0 ? '.inf' : '-.inf'),
nil, nil, true, false, Nodes::Scalar::ANY)
else
@emitter.scalar o.to_s, nil, nil, true, false, Nodes::Scalar::ANY
end
end
def visit_BigDecimal o
@emitter.scalar o._dump, nil, '!ruby/object:BigDecimal', false, false, Nodes::Scalar::ANY
end
def visit_String o
plain = true
quote = true
style = Nodes::Scalar::PLAIN
tag = nil
str = o
if binary?(o)
str = [o].pack('m').chomp
tag = '!binary' # FIXME: change to below when syck is removed
#tag = 'tag:yaml.org,2002:binary'
style = Nodes::Scalar::LITERAL
plain = false
quote = false
elsif o =~ /\n/
style = Nodes::Scalar::LITERAL
elsif o =~ /^\W[^"]*$/
style = Nodes::Scalar::DOUBLE_QUOTED
else
unless String === @ss.tokenize(o)
style = Nodes::Scalar::SINGLE_QUOTED
end
end
ivars = find_ivars o
if ivars.empty?
unless o.class == ::String
tag = "!ruby/string:#{o.class}"
plain = false
quote = false
end
@emitter.scalar str, nil, tag, plain, quote, style
else
maptag = '!ruby/string'
maptag << ":#{o.class}" unless o.class == ::String
register o, @emitter.start_mapping(nil, maptag, false, Nodes::Mapping::BLOCK)
@emitter.scalar 'str', nil, nil, true, false, Nodes::Scalar::ANY
@emitter.scalar str, nil, tag, plain, quote, style
dump_ivars o
@emitter.end_mapping
end
end
def visit_Module o
raise TypeError, "can't dump anonymous module: #{o}" unless o.name
register o, @emitter.scalar(o.name, nil, '!ruby/module', false, false, Nodes::Scalar::SINGLE_QUOTED)
end
def visit_Class o
raise TypeError, "can't dump anonymous class: #{o}" unless o.name
register o, @emitter.scalar(o.name, nil, '!ruby/class', false, false, Nodes::Scalar::SINGLE_QUOTED)
end
def visit_Range o
register o, @emitter.start_mapping(nil, '!ruby/range', false, Nodes::Mapping::BLOCK)
['begin', o.begin, 'end', o.end, 'excl', o.exclude_end?].each do |m|
accept m
end
@emitter.end_mapping
end
def visit_Hash o
tag = o.class == ::Hash ? nil : "!ruby/hash:#{o.class}"
implicit = !tag
register(o, @emitter.start_mapping(nil, tag, implicit, Psych::Nodes::Mapping::BLOCK))
o.each do |k,v|
accept k
accept v
end
@emitter.end_mapping
end
def visit_Psych_Set o
register(o, @emitter.start_mapping(nil, '!set', false, Psych::Nodes::Mapping::BLOCK))
o.each do |k,v|
accept k
accept v
end
@emitter.end_mapping
end
def visit_Array o
if o.class == ::Array
register o, @emitter.start_sequence(nil, nil, true, Nodes::Sequence::BLOCK)
o.each { |c| accept c }
@emitter.end_sequence
else
visit_array_subclass o
end
end
def visit_NilClass o
@emitter.scalar('', nil, 'tag:yaml.org,2002:null', true, false, Nodes::Scalar::ANY)
end
def visit_Symbol o
@emitter.scalar ":#{o}", nil, nil, true, false, Nodes::Scalar::ANY
end
private
# FIXME: Remove the index and count checks in Psych 3.0
NULL = "\x00"
BINARY_RANGE = "\x00-\x7F"
WS_RANGE = "^ -~\t\r\n"
def binary? string
(string.encoding == Encoding::ASCII_8BIT && !string.ascii_only?) ||
string.index(NULL) ||
string.count(BINARY_RANGE, WS_RANGE).fdiv(string.length) > 0.3
end
def visit_array_subclass o
tag = "!ruby/array:#{o.class}"
if o.instance_variables.empty?
node = @emitter.start_sequence(nil, tag, false, Nodes::Sequence::BLOCK)
register o, node
o.each { |c| accept c }
@emitter.end_sequence
else
node = @emitter.start_mapping(nil, tag, false, Nodes::Sequence::BLOCK)
register o, node
# Dump the internal list
accept 'internal'
@emitter.start_sequence(nil, nil, true, Nodes::Sequence::BLOCK)
o.each { |c| accept c }
@emitter.end_sequence
# Dump the ivars
accept 'ivars'
@emitter.start_mapping(nil, nil, true, Nodes::Sequence::BLOCK)
o.instance_variables.each do |ivar|
accept ivar
accept o.instance_variable_get ivar
end
@emitter.end_mapping
@emitter.end_mapping
end
end
def dump_list o
end
# '%:z' was no defined until 1.9.3
if RUBY_VERSION < '1.9.3'
def format_time time
formatted = time.strftime("%Y-%m-%d %H:%M:%S.%9N")
if time.utc?
formatted += " Z"
else
zone = time.strftime('%z')
formatted += " #{zone[0,3]}:#{zone[3,5]}"
end
formatted
end
else
def format_time time
if time.utc?
time.strftime("%Y-%m-%d %H:%M:%S.%9N Z")
else
time.strftime("%Y-%m-%d %H:%M:%S.%9N %:z")
end
end
end
# FIXME: remove this method once "to_yaml_properties" is removed
def find_ivars target
begin
loc = target.method(:to_yaml_properties).source_location.first
unless loc.start_with?(Psych::DEPRECATED) || loc.end_with?('rubytypes.rb')
if $VERBOSE
warn "#{loc}: to_yaml_properties is deprecated, please implement \"encode_with(coder)\""
end
return target.to_yaml_properties
end
rescue
# public_method or source_location might be overridden,
# and it's OK to skip it since it's only to emit a warning.
end
target.instance_variables
end
def register target, yaml_obj
@st.register target, yaml_obj
yaml_obj
end
def dump_coder o
@coders << o
tag = Psych.dump_tags[o.class]
unless tag
klass = o.class == Object ? nil : o.class.name
tag = ['!ruby/object', klass].compact.join(':')
end
c = Psych::Coder.new(tag)
o.encode_with(c)
emit_coder c
end
def emit_coder c
case c.type
when :scalar
@emitter.scalar c.scalar, nil, c.tag, c.tag.nil?, false, Nodes::Scalar::ANY
when :seq
@emitter.start_sequence nil, c.tag, c.tag.nil?, Nodes::Sequence::BLOCK
c.seq.each do |thing|
accept thing
end
@emitter.end_sequence
when :map
@emitter.start_mapping nil, c.tag, c.implicit, c.style
c.map.each do |k,v|
accept k
accept v
end
@emitter.end_mapping
when :object
accept c.object
end
end
def dump_ivars target
ivars = find_ivars target
ivars.each do |iv|
@emitter.scalar("#{iv.to_s.sub(/^@/, '')}", nil, nil, true, false, Nodes::Scalar::ANY)
accept target.instance_variable_get(iv)
end
end
end
end
end