variable.c: $1..$9 in global_variables

* variable.c (rb_f_global_variables): add $1..$9 only if $~ is
  set.  fix the condition removed at r14014.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53530 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 23 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 90c30c6584..468c302307 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Thu Jan 14 11:44:29 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* variable.c (rb_f_global_variables): add $1..$9 only if $~ is
+	  set.  fix the condition removed at r14014.
+
 Wed Jan 13 17:21:45 2016  SHIBATA Hiroshi  <hsbt@ruby-lang.org>
 
 	* .travis.yml: removed commented-out code.
diff --git a/test/ruby/test_variable.rb b/test/ruby/test_variable.rb
index 667f9ee24f..90afde19cb 100644
--- a/test/ruby/test_variable.rb
+++ b/test/ruby/test_variable.rb
@@ -100,6 +100,16 @@ class TestVariable < Test::Unit::TestCase
     assert_equal([:x, :bug9486], x)
   end
 
+  def test_global_variables
+    gv = global_variables
+    assert_empty(gv.grep(/\A(?!\$)/))
+    assert_nil($~)
+    assert_not_include(gv, :$1)
+    /.*/ =~ "global"
+    assert_not_nil($~)
+    assert_include(global_variables-gv, :$1)
+  end
+
   def test_global_variable_0
     assert_in_out_err(["-e", "$0='t'*1000;print $0"], "", /\At+\z/, [])
   end
diff --git a/variable.c b/variable.c
index 842006ed71..26d9a4b944 100644
--- a/variable.c
+++ b/variable.c
@@ -880,14 +880,16 @@ VALUE
 rb_f_global_variables(void)
 {
     VALUE ary = rb_ary_new();
-    char buf[2];
-    int i;
 
     rb_id_table_foreach(rb_global_tbl, gvar_i, (void *)ary);
-    buf[0] = '$';
-    for (i = 1; i <= 9; ++i) {
-	buf[1] = (char)(i + '0');
-	rb_ary_push(ary, ID2SYM(rb_intern2(buf, 2)));
+    if (!NIL_P(rb_backref_get())) {
+	char buf[2];
+	int i;
+	buf[0] = '$';
+	for (i = 1; i <= 9; ++i) {
+	    buf[1] = (char)(i + '0');
+	    rb_ary_push(ary, ID2SYM(rb_intern2(buf, 2)));
+	}
     }
     return ary;
 }