array.c: prefer lhs elements

* array.c (rb_ary_or): lhs elements are prefered, so should not
  replace with rhs elements.
* test/ruby/test_array.rb (test_OR_in_order): import the test failed
  by r43969 from rubyspec/core/array/union_spec.rb.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44015 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,11 @@
+Thu Dec  5 21:53:29 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* array.c (rb_ary_or): lhs elements are prefered, so should not
+	  replace with rhs elements.
+
+	* test/ruby/test_array.rb (test_OR_in_order): import the test failed
+	  by r43969 from rubyspec/core/array/union_spec.rb.
+
 Thu Dec  5 21:05:42 2013  Koichi Sasada  <ko1@atdot.net>
 
 	* gc.c (gc_info_decode): fix to avoid syntax error on VS2012.

array.c

@@ -4025,6 +4025,14 @@ rb_ary_and(VALUE ary1, VALUE ary2)
     return ary3;
 }
 
+static int
+ary_hash_orset(st_data_t *key, st_data_t *value, st_data_t arg, int existing)
+{
+    if (existing) return ST_STOP;
+    *key = *value = (VALUE)arg;
+    return ST_CONTINUE;
+}
+
 /*
  *  call-seq:
  *     ary | other_ary     -> new_ary
@@ -4043,9 +4051,17 @@ static VALUE
 rb_ary_or(VALUE ary1, VALUE ary2)
 {
     VALUE hash, ary3;
+    long i;
 
     ary2 = to_ary(ary2);
-    hash = ary_add_hash(ary_make_hash(ary1), ary2);
+    hash = ary_make_hash(ary1);
+
+    for (i=0; i<RARRAY_LEN(ary2); i++) {
+	VALUE elt = RARRAY_AREF(ary2, i);
+	if (!st_update(RHASH_TBL(hash), (st_data_t)elt, ary_hash_orset, (st_data_t)elt)) {
+	    OBJ_WRITTEN(hash, Qundef, elt);
+	}
+    }
     ary3 = rb_hash_values(hash);
     ary_recycle_hash(hash);
     return ary3;

test/ruby/test_array.rb

@@ -1662,6 +1662,18 @@ class TestArray < Test::Unit::TestCase
     assert(c.none?(&:frozen?))
   end
 
+  def test_OR_in_order
+    obj1, obj2 = Class.new do
+      attr_reader :name
+      def initialize(name) @name = name; end
+      def inspect; "test_OR_in_order(#{@name})"; end
+      def hash; 0; end
+      def eql?(a) true; end
+      break [new("1"), new("2")]
+    end
+    assert_equal([obj1], [obj1]|[obj2])
+  end
+
   def test_combination
     assert_equal(@cls[[]], @cls[1,2,3,4].combination(0).to_a)
     assert_equal(@cls[[1],[2],[3],[4]], @cls[1,2,3,4].combination(1).to_a)