Merge pull request #69 from ManageIQ/register_strings_for_use_in_aliases

From yaml, register a newly created String with aliases.  To yaml, register Strings containing ivars with aliases.

lib/psych/visitors/to_ruby.rb

@@ -148,6 +148,7 @@ def visit_Psych_Nodes_Mapping o
 
           if klass
             string = klass.allocate.replace string
+            register(o, string)
           end
 
           init_with(string, members.map { |k,v| [k.to_s.sub(/^@/, ''),v] }, o)

lib/psych/visitors/yaml_tree.rb

@@ -254,7 +254,7 @@ def visit_String o
           maptag = '!ruby/string'
           maptag << ":#{o.class}" unless o.class == ::String
 
-          @emitter.start_mapping nil, maptag, false, Nodes::Mapping::BLOCK
+          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
 

test/psych/test_alias_and_anchor.rb

@@ -1,5 +1,13 @@
 require 'psych/helper'
 
+class ObjectWithInstanceVariables
+  attr_accessor :var1, :var2
+end
+
+class SubStringWithInstanceVariables < String
+  attr_accessor :var1
+end
+
 module Psych
  class TestAliasAndAnchor < TestCase
    def test_mri_compatibility
@@ -14,6 +22,40 @@ def test_mri_compatibility
      result.each {|el| assert_same(result[0], el) }
    end
 
+   def test_mri_compatibility_object_with_ivars
+  yaml = <<EOYAML
+--- 
+- &id001 !ruby/object:ObjectWithInstanceVariables 
+  var1: test1
+  var2: test2
+- *id001
+- *id001
+EOYAML
+
+     result = Psych.load yaml
+     result.each do |el| 
+      assert_same(result[0], el)
+      assert_equal('test1', el.var1)
+      assert_equal('test2', el.var2)
+    end
+   end
+
+   def test_mri_compatibility_substring_with_ivars
+    yaml = <<EOYAML
+--- 
+- &id001 !str:SubStringWithInstanceVariables 
+  str: test
+  "@var1": test
+- *id001
+- *id001
+EOYAML
+     result = Psych.load yaml
+     result.each do |el|
+      assert_same(result[0], el)
+      assert_equal('test', el.var1)
+    end
+   end
+
    def test_anchor_alias_round_trip
      o = Object.new
      original = [o,o,o]
@@ -22,5 +64,33 @@ def test_anchor_alias_round_trip
      result = Psych.load yaml
      result.each {|el| assert_same(result[0], el) }
    end
+
+   def test_anchor_alias_round_trip_object_with_ivars
+     o = ObjectWithInstanceVariables.new
+     o.var1 = 'test1'
+     o.var2 = 'test2'
+     original = [o,o,o]
+
+     yaml = Psych.dump original
+     result = Psych.load yaml
+     result.each do |el|
+      assert_same(result[0], el)
+      assert_equal('test1', el.var1)
+      assert_equal('test2', el.var2)
+    end
+   end
+
+   def test_anchor_alias_round_trip_substring_with_ivars
+     o = SubStringWithInstanceVariables.new
+     o.var1 = 'test'
+     original = [o,o,o]
+
+     yaml = Psych.dump original
+     result = Psych.load yaml
+     result.each do |el|
+      assert_same(result[0], el)
+      assert_equal('test', el.var1)
+    end
+   end
  end
 end