From f4386413f16f9e492a74f6b65e981e20e22c4849 Mon Sep 17 00:00:00 2001
From: Robert Schulze <robert@dotless.de>
Date: Wed, 5 Feb 2020 10:59:13 +0100
Subject: [PATCH] Cope with frozen-string-literal

When running irb 1.2.1 (2019-12-24) with frozen-string-literal enabled, it crashes in reline with `can't modify frozen String (FrozenError)`

Steps to reproduce:

`RUBYOPT="--enable-frozen-string-literal" irb`
---
 lib/reline/ansi.rb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/reline/ansi.rb b/lib/reline/ansi.rb
index 0b1a7e1745..0fddbcc854 100644
--- a/lib/reline/ansi.rb
+++ b/lib/reline/ansi.rb
@@ -172,7 +172,7 @@ class Reline::ANSI
 
   def self.cursor_pos
     begin
-      res = ''
+      res = String.new
       m = nil
       @@input.raw do |stdin|
         @@output << "\e[6n"