* ext/psych/lib/psych/deprecated.rb: implementing Psych.quick_emit and

adding deprecation warnings.
* ext/psych/lib/psych/visitors/to_ruby.rb: supporting deprecated
  yaml_initialize api.
* ext/psych/lib/psych/visitors/yaml_tree.rb: supporting deprecated
  to_yaml api.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@27279 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/psych/lib/psych/deprecated.rb

@@ -0,0 +1,19 @@
+module Psych
+  module DeprecatedMethods # :nodoc:
+    attr_accessor :taguri
+    attr_accessor :to_yaml_style
+  end
+
+  def self.quick_emit thing, opts = {}, &block # :nodoc:
+    warn "#{caller[0]}: YAML.quick_emit is deprecated" if $VERBOSE && !caller[0].start_with?(File.dirname(__FILE__))
+    target = eval 'self', block.binding
+    target.extend DeprecatedMethods
+    metaclass = class << target; self; end
+    metaclass.send(:define_method, :encode_with) do |coder|
+      target.taguri        = coder.tag
+      target.to_yaml_style = coder.style
+      block.call coder
+    end
+    target.psych_to_yaml unless opts[:nodump]
+  end
+end

test/psych/test_deprecated.rb

@@ -0,0 +1,135 @@
+require_relative 'helper'
+
+module Psych
+  class TestDeprecated < TestCase
+    class QuickEmitter
+      attr_reader :name
+      attr_reader :value
+
+      def initialize
+        @name  = 'hello!!'
+        @value = 'Friday!'
+      end
+
+      def to_yaml opts = {}
+        Psych.quick_emit object_id, opts do |out|
+          out.map taguri, to_yaml_style do |map|
+            map.add 'name', @name
+            map.add 'value', nil
+          end
+        end
+      end
+    end
+
+    def setup
+      @qe = QuickEmitter.new
+    end
+
+    def test_quick_emit
+      qe2 = Psych.load @qe.to_yaml
+      assert_equal @qe.name, qe2.name
+      assert_instance_of QuickEmitter, qe2
+      assert_nil qe2.value
+    end
+
+    def test_recursive_quick_emit
+      hash  = { :qe => @qe }
+      hash2 = Psych.load Psych.dump hash
+      qe    = hash2[:qe]
+
+      assert_equal @qe.name, qe.name
+      assert_instance_of QuickEmitter, qe
+      assert_nil qe.value
+    end
+
+    class QuickEmitterEncodeWith
+      attr_reader :name
+      attr_reader :value
+
+      def initialize
+        @name  = 'hello!!'
+        @value = 'Friday!'
+      end
+
+      def encode_with coder
+        coder.map do |map|
+          map.add 'name', @name
+          map.add 'value', nil
+        end
+      end
+
+      def to_yaml opts = {}
+        raise
+      end
+    end
+
+    ###
+    # An object that defines both to_yaml and encode_with should only call
+    # encode_with.
+    def test_recursive_quick_emit_encode_with
+      qeew = QuickEmitterEncodeWith.new
+      hash  = { :qe => qeew }
+      hash2 = Psych.load Psych.dump hash
+      qe    = hash2[:qe]
+
+      assert_equal qeew.name, qe.name
+      assert_instance_of QuickEmitterEncodeWith, qe
+      assert_nil qe.value
+    end
+
+    class YamlInit
+      attr_reader :name
+      attr_reader :value
+
+      def initialize
+        @name  = 'hello!!'
+        @value = 'Friday!'
+      end
+
+      def yaml_initialize tag, vals
+        vals.each { |ivar, val| instance_variable_set "@#{ivar}", 'TGIF!' }
+      end
+    end
+
+    def test_yaml_initialize
+      hash  = { :yi => YamlInit.new }
+      hash2 = Psych.load Psych.dump hash
+      yi    = hash2[:yi]
+
+      assert_equal 'TGIF!', yi.name
+      assert_equal 'TGIF!', yi.value
+      assert_instance_of YamlInit, yi
+    end
+
+    class YamlInitAndInitWith
+      attr_reader :name
+      attr_reader :value
+
+      def initialize
+        @name  = 'shaners'
+        @value = 'Friday!'
+      end
+
+      def init_with coder
+        coder.map.each { |ivar, val| instance_variable_set "@#{ivar}", 'TGIF!' }
+      end
+
+      def yaml_initialize tag, vals
+        raise
+      end
+    end
+
+    ###
+    # An object that implements both yaml_initialize and init_with should not
+    # receive the yaml_initialize call.
+    def test_yaml_initialize_and_init_with
+      hash  = { :yi => YamlInitAndInitWith.new }
+      hash2 = Psych.load Psych.dump hash
+      yi    = hash2[:yi]
+
+      assert_equal 'TGIF!', yi.name
+      assert_equal 'TGIF!', yi.value
+      assert_instance_of YamlInitAndInitWith, yi
+    end
+  end
+end