Implement a freeze: parser option

If set to true all parsed objects will be
immediately frozen, and strings will be
deduplicated if the Ruby implementation
allows it.

1 files changed, 21 insertions, 0 deletions

diff --git a/test/json/json_parser_test.rb b/test/json/json_parser_test.rb
index 514441efce..e29f3f126f 100644
--- a/test/json/json_parser_test.rb
+++ b/test/json/json_parser_test.rb
@@ -218,6 +218,17 @@ class JSONParserTest < Test::Unit::TestCase
     end
   end
 
+  def test_freeze
+    assert_predicate parse('{}', :freeze => true), :frozen?
+    assert_predicate parse('[]', :freeze => true), :frozen?
+    assert_predicate parse('"foo"', :freeze => true), :frozen?
+    
+    if string_deduplication_available?
+      assert_same -'foo', parse('"foo"', :freeze => true)
+      assert_same -'foo', parse('{"foo": 1}', :freeze => true).keys.first
+    end
+  end
+
   def test_parse_comments
     json = <<EOT
 {
@@ -468,6 +479,16 @@ EOT
 
   private
 
+  def string_deduplication_available?
+    r1 = rand.to_s
+    r2 = r1.dup
+    begin
+      (-r1).equal?(-r2)
+    rescue NoMethodError
+      false # No String#-@
+    end
+  end
+
   def assert_equal_float(expected, actual, delta = 1e-2)
     Array === expected and expected = expected.first
     Array === actual and actual = actual.first