* class.c (rb_include_module): revert duplicate inclusion of

  modules.  [ruby-dev:29793]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@11291 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

4 files changed, 28 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index 7bc5689428..9c096ceaba 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Nov  7 17:52:08 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
+
+	* class.c (rb_include_module): revert duplicate inclusion of
+	  modules.  [ruby-dev:29793]
+
 Tue Nov  7 17:18:11 2006  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* eval.c (method_missing): update old argument adjustment.
diff --git a/class.c b/class.c
index c204fdd41b..c7fc1df370 100644
--- a/class.c
+++ b/class.c
@@ -344,7 +344,7 @@ include_class_new(VALUE module, VALUE super)
 void
 rb_include_module(VALUE klass, VALUE module)
 {
-    VALUE c;
+    VALUE p, c;
     int changed = 0;
 
     rb_frozen_class_p(klass);
@@ -359,11 +359,29 @@ rb_include_module(VALUE klass, VALUE module)
     OBJ_INFECT(klass, module);
     c = klass;
     while (module) {
+	int superclass_seen = Qfalse;
+
 	if (RCLASS(klass)->m_tbl == RCLASS(module)->m_tbl)
 	    rb_raise(rb_eArgError, "cyclic include detected");
-	RCLASS(c)->super = include_class_new(module, RCLASS(c)->super);
-	c = RCLASS(c)->super;
+	/* ignore if the module included already in superclasses */
+	for (p = RCLASS(klass)->super; p; p = RCLASS(p)->super) {
+	    switch (BUILTIN_TYPE(p)) {
+	      case T_ICLASS:
+		if (RCLASS(p)->m_tbl == RCLASS(module)->m_tbl) {
+		    if (!superclass_seen) {
+			c = p;	/* move insertion point */
+		    }
+		    goto skip;
+		}
+		break;
+	      case T_CLASS:
+		superclass_seen = Qtrue;
+		break;
+	    }
+	}
+	c = RCLASS(c)->super = include_class_new(module, RCLASS(c)->super);
 	changed = 1;
+      skip:
 	module = RCLASS(module)->super;
     }
     if (changed) rb_clear_cache();
diff --git a/sample/test.rb b/sample/test.rb
index a32dbcbec2..aad5a094c3 100644
--- a/sample/test.rb
+++ b/sample/test.rb
@@ -1939,7 +1939,7 @@ module M003; include M002; end
 module M002; include M001; end
 module M003; include M002; end
 
-test_ok(M003.ancestors == [M003, M002, M001, M002])
+test_ok(M003.ancestors == [M003, M002, M001])
 
 test_check "marshal"
 $x = [1,2,3,[4,5,"foo"],{1=>"bar"},2.5,fact(30)]
diff --git a/test/ruby/test_clone.rb b/test/ruby/test_clone.rb
index 67d79fb8a5..43c0cffa1d 100644
--- a/test/ruby/test_clone.rb
+++ b/test/ruby/test_clone.rb
@@ -23,6 +23,6 @@ class TestClone < Test::Unit::TestCase
 
     assert_raises(NoMethodError) {foo.test2}
 
-    assert_equal([M003, M002, M001, M002], M003.ancestors)
+    assert_equal([M003, M002, M001], M003.ancestors)
   end
 end