From b0986a8f827cc97d7cf19b15c38fbdab794e34b9 Mon Sep 17 00:00:00 2001
From: ko1 <ko1@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Tue, 27 Nov 2007 04:43:54 +0000
Subject: [PATCH] * compile.c, insns.def: change return value of "defined?"  
 for $&, $1, ... .  If such variables are defined,   return "global-variable".
 * test/ruby/test_defined.rb: add tests. * bootstraptest/test_syntax.rb: fix a
 test.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@14031 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 ChangeLog                    | 10 ++++++++++
 bootstraptest/test_syntax.rb |  2 +-
 compile.c                    |  4 +++-
 insns.def                    | 11 +++--------
 test/ruby/test_defined.rb    | 29 +++++++++++++++++++++++++++++
 5 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 3ad79e2891..94910dd5e4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+Tue Nov 27 12:47:23 2007  Koichi Sasada  <ko1@atdot.net>
+
+	* compile.c, insns.def: change return value of "defined?"
+	  for $&, $1, ... .  If such variables are defined,
+	  return "global-variable".
+
+	* test/ruby/test_defined.rb: add tests.
+
+	* bootstraptest/test_syntax.rb: fix a test.
+
 Tue Nov 27 11:54:46 2007  Koichi Sasada  <ko1@atdot.net>
 
 	* insns.def: fix typo.
diff --git a/bootstraptest/test_syntax.rb b/bootstraptest/test_syntax.rb
index 9541d67089..b1517e697b 100644
--- a/bootstraptest/test_syntax.rb
+++ b/bootstraptest/test_syntax.rb
@@ -248,7 +248,7 @@ assert_equal %q{["method", "method", "method", "method", nil, nil, "method", "me
   end
   C.new.test + [defined?(C.new.m3)]
 }
-assert_equal %q{[nil, nil, nil, nil, "$1", "$2", nil, nil]}, %q{
+assert_equal %q{[nil, nil, nil, nil, "global-variable", "global-variable", nil, nil]}, %q{
   $ans = [defined?($1), defined?($2), defined?($3), defined?($4)]
   /(a)(b)/ =~ 'ab'
   $ans + [defined?($1), defined?($2), defined?($3), defined?($4)]
diff --git a/compile.c b/compile.c
index 9a096ccf61..2c27d60d6e 100644
--- a/compile.c
+++ b/compile.c
@@ -2333,10 +2333,12 @@ defined_expr(rb_iseq_t *iseq, LINK_ANCHOR *ret,
 		  needstr);
 	return 1;
 
+      case NODE_BACK_REF:
       case NODE_NTH_REF:
 	ADD_INSN(ret, nd_line(node), putnil);
 	ADD_INSN3(ret, nd_line(node), defined, INT2FIX(DEFINED_REF),
-		  INT2FIX(node->nd_nth), needstr);
+		  INT2FIX(node->nd_nth << 1 | type == NODE_BACK_REF),
+		  needstr);
 	return 1;
 
       case NODE_ZSUPER:
diff --git a/insns.def b/insns.def
index 4e7ba8b352..489a90da09 100644
--- a/insns.def
+++ b/insns.def
@@ -795,8 +795,6 @@ defined
 {
     VALUE klass;
     char *expr_type = 0;
-    char buf[0x10];
-    
     val = Qnil;
 
     switch (type) {
@@ -868,12 +866,9 @@ defined
 	  break;
       }
       case DEFINED_REF:{
-	  int nth = FIX2INT(obj);
-	  VALUE backref = lfp_svar_get(th, GET_LFP(), 1);
-	  
-	  if (rb_reg_nth_match(nth, backref) != Qnil) {
-	      snprintf(buf, 0x10, "$%d", nth);
-	      expr_type = buf;
+	  val = vm_getspecial(th, GET_LFP(), Qfalse, FIX2INT(obj));
+	  if (val != Qnil) {
+	      expr_type = "global-variable";
 	  }
 	  break;
       }
diff --git a/test/ruby/test_defined.rb b/test/ruby/test_defined.rb
index 84b9bf7b9e..bfcd7fb667 100644
--- a/test/ruby/test_defined.rb
+++ b/test/ruby/test_defined.rb
@@ -48,5 +48,34 @@ class TestDefined < Test::Unit::TestCase
 
     assert(defined_test)		# not iterator
     assert(!defined_test{})	        # called as iterator
+
+    /a/ =~ ''
+    assert_equal nil, defined?($&)
+    assert_equal nil, defined?($`)
+    assert_equal nil, defined?($')
+    assert_equal nil, defined?($+)
+    assert_equal nil, defined?($1)
+    assert_equal nil, defined?($2)
+    /a/ =~ 'a'
+    assert_equal 'global-variable', defined?($&)
+    assert_equal 'global-variable', defined?($`)
+    assert_equal 'global-variable', defined?($')
+    assert_equal nil, defined?($+)
+    assert_equal nil, defined?($1)
+    assert_equal nil, defined?($2)
+    /(a)/ =~ 'a'
+    assert_equal 'global-variable', defined?($&)
+    assert_equal 'global-variable', defined?($`)
+    assert_equal 'global-variable', defined?($')
+    assert_equal 'global-variable', defined?($+)
+    assert_equal 'global-variable', defined?($1)
+    assert_equal nil, defined?($2)
+    /(a)b/ =~ 'ab'
+    assert_equal 'global-variable', defined?($&)
+    assert_equal 'global-variable', defined?($`)
+    assert_equal 'global-variable', defined?($')
+    assert_equal 'global-variable', defined?($+)
+    assert_equal 'global-variable', defined?($1)
+    assert_equal nil, defined?($2)
   end
 end