finish the field access

now that fields can be defined

test/compiler/test_all.rb

@@ -2,3 +2,4 @@ require_relative "test_basic"
 require_relative "test_methods"
 require_relative "test_hello"
 require_relative "test_compiler"
+require_relative "test_field_access"

test/compiler/test_field_access.rb

@@ -7,13 +7,13 @@ module Virtual
 
     def test_foo2
       @string_input = <<HERE
-int a
+field int a
 int foo(int x)
   int b = self.a
   return b +x
 end
 HERE
-      @expect =  [ Virtual::Return ]
+      @output =  [ [Virtual::MethodEnter] , [Virtual::MethodReturn] ]
       check
     end