* hash.c (rb_hash_set_default_proc): Accept nil, patch by Run Paint

[Feature #4234]

* test/ruby/test_hash.rb: test for above.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@35268 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,10 @@
+Mon Apr  9 13:06:58 2012  Marc-Andre Lafortune  <ruby-core@marc-andre.ca>
+
+	* hash.c (rb_hash_set_default_proc): Accept nil, patch by Run Paint
+	  [Feature #4234]
+
+	* test/ruby/test_hash.rb: test for above.
+
 Mon Apr  9 08:01:15 2012  Tadayoshi Funaba  <tadf@dotrb.org>
 
 	* ext/date/date_strftime.c: gets the value with range() consistetly.

NEWS

@@ -21,6 +21,10 @@ with all sufficient information, see the ChangeLog file.
     * added method:
       * added Enumerable#lazy method for lazy enumeration.
 
+  * Hash
+    * extended method:
+      * Hash#default_proc= can be passed nil to clear the default proc.
+
   * Kernel
     * added method:
       * added Kernel#Hash conversion method like Array() or Float().

hash.c

@@ -689,9 +689,9 @@ rb_hash_default_proc(VALUE hash)
 
 /*
  *  call-seq:
- *     hsh.default_proc = proc_obj     -> proc_obj
+ *     hsh.default_proc = proc_obj or nil
  *
- *  Sets the default proc to be executed on each key lookup.
+ *  Sets the default proc to be executed on each failed key lookup.
  *
  *     h.default_proc = proc do |hash, key|
  *       hash[key] = key + key
@@ -706,6 +706,11 @@ rb_hash_set_default_proc(VALUE hash, VALUE proc)
     VALUE b;
 
     rb_hash_modify_check(hash);
+    if (NIL_P(proc)) {
+	FL_UNSET(hash, HASH_PROC_DEFAULT);
+	RHASH_IFNONE(hash) = proc;
+	return proc;
+    }
     b = rb_check_convert_type(proc, T_DATA, "Proc", "to_proc");
     if (NIL_P(b) || !rb_obj_is_proc(b)) {
 	rb_raise(rb_eTypeError,

test/ruby/test_hash.rb

@@ -718,6 +718,10 @@ class TestHash < Test::Unit::TestCase
   def test_default_proc
     h = Hash.new {|hh, k| hh + k + "baz" }
     assert_equal("foobarbaz", h.default_proc.call("foo", "bar"))
+    assert_nil(h.default_proc = nil)
+    assert_nil(h.default_proc)
+    h.default_proc = ->(h, k){ true }
+    assert(h[:nope])
     h = {}
     assert_nil(h.default_proc)
   end