test_mwrap: fix test reliability

Not sure what drugs I was on when I wrote this :x

1 files changed, 4 insertions, 1 deletions

diff --git a/test/test_mwrap.rb b/test/test_mwrap.rb
index 29bbdd2..176dca6 100644
--- a/test/test_mwrap.rb
+++ b/test/test_mwrap.rb
@@ -5,6 +5,7 @@ require 'test/unit'
 require 'mwrap'
 require 'rbconfig'
 require 'tempfile'
+require 'io/wait'
 
 class TestMwrap < Test::Unit::TestCase
   RB = "#{RbConfig::CONFIG['bindir']}/#{RbConfig::CONFIG['RUBY_INSTALL_NAME']}"
@@ -128,10 +129,12 @@ class TestMwrap < Test::Unit::TestCase
         assert_equal "\n", r.gets
         buf = +''
         10.times { Process.kill(:USR1, pid) }
-        while IO.select([r], nil, nil, 0.1)
+        while r.wait_readable(0.1)
           case tmp = r.read_nonblock(1000, exception: false)
           when String
             buf << tmp
+          when nil
+            break
           end
         end
         w2.close