strscan.c: fix segfault in aref

* ext/strscan/strscan.c (strscan_aref): fix segfault after
  get_byte or getch which do not apply regexp.
  [ruby-core:82116] [Bug #13759]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59384 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 10 insertions, 0 deletions

diff --git a/test/strscan/test_stringscanner.rb b/test/strscan/test_stringscanner.rb
index bc5db7900a..9fe6ad7125 100644
--- a/test/strscan/test_stringscanner.rb
+++ b/test/strscan/test_stringscanner.rb
@@ -718,4 +718,14 @@ class TestStringScanner < Test::Unit::TestCase
     s.scan(/test strin/)
     assert_equal('#<StringScanner 10/16 "...strin" @ "g tes...">', s.inspect)
   end
+
+  def test_aref_without_regex
+    s = StringScanner.new('abc')
+    s.get_byte
+    assert_nil(s[:c])
+    assert_nil(s["c"])
+    s.getch
+    assert_nil(s[:c])
+    assert_nil(s["c"])
+  end
 end