From 792d1deb949e8416d7a76d66771b286d35c8278d Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Sat, 29 Jun 2019 19:07:25 +0900
Subject: [PATCH] Escape control codes in regexp warning message

---
 regerror.c               | 3 ++-
 test/ruby/test_regexp.rb | 2 ++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/regerror.c b/regerror.c
index 59cf53068e..efcfefffdf 100644
--- a/regerror.c
+++ b/regerror.c
@@ -356,7 +356,8 @@ onig_vsnprintf_with_pattern(UChar buf[], int bufsize, OnigEncoding enc,
 	*s++ = *p++;
       }
       else if (!ONIGENC_IS_CODE_PRINT(enc, *p) &&
-	       !ONIGENC_IS_CODE_SPACE(enc, *p)) {
+	       (!ONIGENC_IS_CODE_SPACE(enc, *p) ||
+                ONIGENC_IS_CODE_CNTRL(enc, *p))) {
 	sprint_byte_with_x((char* )bs, (unsigned int )(*p++));
 	len = onigenc_str_bytelen_null(ONIG_ENCODING_ASCII, bs);
         bp = bs;
diff --git a/test/ruby/test_regexp.rb b/test/ruby/test_regexp.rb
index 18a6d4d7c9..6cfd7df824 100644
--- a/test/ruby/test_regexp.rb
+++ b/test/ruby/test_regexp.rb
@@ -1124,6 +1124,8 @@ class TestRegexp < Test::Unit::TestCase
 
     bug8151 = '[ruby-core:53649]'
     assert_warning(/\A\z/, bug8151) { Regexp.new('(?:[\u{33}])').to_s }
+
+    assert_warning(%r[/.*/\Z]) { Regexp.new("[\n\n]") }
   end
 
   def test_property_warn