Merge pull request #2402 from herwinw/marshal_load_object_link

Fix object links in Marshal.load

spec/core/marshal/shared/load.rb

@@ -393,11 +393,9 @@
         str = "string"
 
         # this string represents: [<#UserDefinedImmediate A>, <#String "string">, <#String "string">]
-        NATFIXME 'loads an array containing an instance of the object, followed by multiple instances of another object', exception: ArgumentError, message: 'dump format error' do
-          marshaled_obj = Marshal.send(@method, "\004\b[\bu:\031UserDefinedImmediate\000\"\vstring@\a")
+        marshaled_obj = Marshal.send(@method, "\004\b[\bu:\031UserDefinedImmediate\000\"\vstring@\a")
 
-          marshaled_obj.should == [nil, str, str]
-        end
+        marshaled_obj.should == [nil, str, str]
       end
 
       it "loads any structure with multiple references to the same object, followed by multiple instances of another object" do
@@ -554,12 +552,10 @@
       s.instance_variable_set(:@foo, 10)
       obj = ['5', s, 'hi'].extend(Meths, MethsMore)
       obj.instance_variable_set(:@mix, s)
-      NATFIXME 'loads an array having ivar', exception: ArgumentError, message: 'dump format error' do
-        new_obj = Marshal.send(@method, "\004\bI[\b\"\0065I\"\twell\006:\t@fooi\017\"\ahi\006:\t@mix@\a")
-        new_obj.should == obj
-        new_obj.instance_variable_get(:@mix).should equal new_obj[1]
-        new_obj[1].instance_variable_get(:@foo).should == 10
-      end
+      new_obj = Marshal.send(@method, "\004\bI[\b\"\0065I\"\twell\006:\t@fooi\017\"\ahi\006:\t@mix@\a")
+      new_obj.should == obj
+      new_obj.instance_variable_get(:@mix).should equal new_obj[1]
+      new_obj[1].instance_variable_get(:@foo).should == 10
     end
 
     it "loads an extended Array object containing a user-marshaled object" do
@@ -733,9 +729,7 @@
     it "loads a string having ivar with ref to self" do
       obj = +'hi'
       obj.instance_variable_set(:@self, obj)
-      NATFIXME 'loads a string having ivar with ref to self', exception: ArgumentError, message: 'dump format error' do
-        Marshal.send(@method, "\004\bI\"\ahi\006:\n@self@\000").should == obj
-      end
+      Marshal.send(@method, "\004\bI\"\ahi\006:\n@self@\000").should == obj
     end
 
     it "loads a string through StringIO stream" do
@@ -919,13 +913,11 @@ def io.binmode; raise "binmode"; end
       obj = Exception.new("foo")
       obj.instance_variable_set :@arr, arr
 
-      NATFIXME 'Support ivar', exception: ArgumentError, message: 'dump format error' do
-        loaded = Marshal.send(@method, "\x04\bo:\x0EException\b:\tmesg\"\bfoo:\abt0:\t@arr[\t:\aso;\t\"\ahi@\b")
-        new_arr = loaded.instance_variable_get :@arr
+      loaded = Marshal.send(@method, "\x04\bo:\x0EException\b:\tmesg\"\bfoo:\abt0:\t@arr[\t:\aso;\t\"\ahi@\b")
+      new_arr = loaded.instance_variable_get :@arr
 
-        loaded.message.should == obj.message
-        new_arr.should == arr
-      end
+      loaded.message.should == obj.message
+      new_arr.should == arr
     end
   end
 
@@ -952,12 +944,10 @@ def io.binmode; raise "binmode"; end
       obj = Object.new
       obj.instance_variable_set :@str, arr
 
-      NATFIXME 'Support ivar', exception: ArgumentError, message: 'dump format error' do
-        new_obj = Marshal.send(@method, "\004\bo:\vObject\006:\t@str[\t:\aso;\a\"\ahi@\a")
-        new_str = new_obj.instance_variable_get :@str
+      new_obj = Marshal.send(@method, "\004\bo:\vObject\006:\t@str[\t:\aso;\a\"\ahi@\a")
+      new_str = new_obj.instance_variable_get :@str
 
-        new_str.should == arr
-      end
+      new_str.should == arr
     end
 
     it "loads an Object with a non-US-ASCII instance variable" do

src/marshal.rb

@@ -410,6 +410,7 @@ class Reader
     def initialize(source)
       @source = source
       @symbol_lookup = []
+      @object_lookup = []
     end
 
     def read_byte
@@ -435,6 +436,11 @@ def read_version
       end
     end
 
+    def read_object_link
+      index = read_integer
+      @object_lookup.fetch(index)
+    end
+
     def read_signed_byte
       byte = read_byte
       byte > 127 ? (byte - 256) : byte
@@ -644,44 +650,53 @@ def read_value
         true
       when 'F'
         false
+      when '@'
+        read_object_link
       when 'i'
         read_integer
       when 'l'
         read_big_integer
-      when '"'
-        read_string
       when ':'
         read_symbol
       when ';'
         read_symbol_link
       when 'f'
         read_float
-      when '['
-        read_array
-      when '{'
-        read_hash
-      when '}'
-        read_hash_with_default
-      when 'c'
-        read_class
-      when 'm'
-        read_module
-      when '/'
-        read_regexp
-      when 'U'
-        read_user_marshaled_object_with_allocate
-      when 'u'
-        read_user_marshaled_object_without_allocate
-      when 'S'
-        read_struct
-      when 'o'
-        read_object
       when 'I'
         result = read_value
         read_ivars(result) unless result.is_a?(Regexp)
         result
       else
-        raise ArgumentError, 'dump format error'
+        index = @object_lookup.size
+        @object_lookup << nil # placeholder
+        value = case char
+                when '"'
+                  read_string
+                when '['
+                  read_array
+                when '{'
+                  read_hash
+                when '}'
+                  read_hash_with_default
+                when 'c'
+                  read_class
+                when 'm'
+                  read_module
+                when '/'
+                  read_regexp
+                when 'U'
+                  read_user_marshaled_object_with_allocate
+                when 'u'
+                  read_user_marshaled_object_without_allocate
+                when 'S'
+                  read_struct
+                when 'o'
+                  read_object
+                else
+                  raise ArgumentError, 'dump format error'
+                end
+        @object_lookup[index] = value
+        value
       end
     end