Object#clone with freeze: false [Feature #12300]

	* object.c (rb_obj_clone2): Allow Object#clone to take freeze:
	  false keyword argument to not freeze the clone.
  	  [ruby-core:75017][Feature #12300]

 	* test/ruby/test_object.rb (TestObject): test for it.



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55786 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Author: shyouhei

ChangeLog

@@ -1,3 +1,11 @@
+Mon Aug  1 14:50:06 2016  Jeremy Evans <code@jeremyevans.net>
+
+	* object.c (rb_obj_clone2): Allow Object#clone to take freeze:
+	  false keyword argument to not freeze the clone.
+	  [ruby-core:75017][Feature #12300]
+
+	* test/ruby/test_object.rb (TestObject): test for it.
+
 Mon Aug  1 12:16:19 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
 
 	* ext/json/*, test/json/json_parser_test.rb: Update json-2.0.2.

object.c

@@ -299,11 +299,12 @@ init_copy(VALUE dest, VALUE obj)
 
 /*
  *  call-seq:
- *     obj.clone -> an_object
+ *     obj.clone(freeze: true) -> an_object
  *
  *  Produces a shallow copy of <i>obj</i>---the instance variables of
  *  <i>obj</i> are copied, but not the objects they reference.
- *  <code>clone</code> copies the frozen and tainted state of <i>obj</i>.
+ *  <code>clone</code> copies the frozen (unless :freeze keyword argument
+ *  is given with a false value) and tainted state of <i>obj</i>.
  *  See also the discussion under <code>Object#dup</code>.
  *
  *     class Klass
@@ -321,11 +322,25 @@ init_copy(VALUE dest, VALUE obj)
  *  the class.
  */
 
-VALUE
-rb_obj_clone(VALUE obj)
+static VALUE
+rb_obj_clone2(int argc, VALUE *argv, VALUE obj)
 {
+    static ID keyword_ids[1];
+    VALUE opt;
+    VALUE kwargs[1];
     VALUE clone;
     VALUE singleton;
+    VALUE kwfreeze = Qtrue;
+    int n;
+
+    if (!keyword_ids[0]) {
+	CONST_ID(keyword_ids[0], "freeze");
+    }
+    n = rb_scan_args(argc, argv, "0:", &opt);
+    if (!NIL_P(opt)) {
+	rb_get_kwargs(opt, keyword_ids, 0, 1, kwargs);
+	kwfreeze = kwargs[0];
+    }
 
     if (rb_special_const_p(obj)) {
         rb_raise(rb_eTypeError, "can't clone %s", rb_obj_classname(obj));
@@ -342,11 +357,20 @@ rb_obj_clone(VALUE obj)
 
     init_copy(clone, obj);
     rb_funcall(clone, id_init_clone, 1, obj);
-    RBASIC(clone)->flags |= RBASIC(obj)->flags & FL_FREEZE;
+
+    if (Qfalse != kwfreeze) {
+	RBASIC(clone)->flags |= RBASIC(obj)->flags & FL_FREEZE;
+    }
 
     return clone;
 }
 
+VALUE
+rb_obj_clone(VALUE obj)
+{
+    return rb_obj_clone2(0, NULL, obj);
+}
+
 /*
  *  call-seq:
  *     obj.dup -> an_object
@@ -3424,7 +3448,7 @@ InitVM_Object(void)
 
     rb_define_method(rb_mKernel, "class", rb_obj_class, 0);
     rb_define_method(rb_mKernel, "singleton_class", rb_obj_singleton_class, 0);
-    rb_define_method(rb_mKernel, "clone", rb_obj_clone, 0);
+    rb_define_method(rb_mKernel, "clone", rb_obj_clone2, -1);
     rb_define_method(rb_mKernel, "dup", rb_obj_dup, 0);
     rb_define_method(rb_mKernel, "itself", rb_obj_itself, 0);
     rb_define_method(rb_mKernel, "initialize_copy", rb_obj_init_copy, 1);

test/ruby/test_object.rb

@@ -28,6 +28,22 @@ def test_dup
     end
   end
 
+  def test_clone
+    a = Object.new
+    def a.b; 2 end
+    
+    a.freeze
+    c = a.clone
+    assert_equal(true, c.frozen?)
+    assert_equal(2, c.b)
+
+    d = a.clone(freeze: false)
+    def d.e; 3; end
+    assert_equal(false, d.frozen?)
+    assert_equal(2, d.b)
+    assert_equal(3, d.e)
+  end
+
   def test_init_dupclone
     cls = Class.new do
       def initialize_clone(orig); throw :initialize_clone; end