From 28e9344fa49387ef84c71a72d1ba7e32b61cf4c7 Mon Sep 17 00:00:00 2001
From: aycabta <aycabta@gmail.com>
Date: Wed, 23 Dec 2020 20:29:57 +0900
Subject: [PATCH] [ruby/irb] Change StdioInputMethod#eof? to non-blocking

This fixes --inf-ruby-mode.

https://github.com/ruby/irb/commit/0e4a818955
---
 lib/irb/input-method.rb | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/lib/irb/input-method.rb b/lib/irb/input-method.rb
index 6e87488753..61540a106f 100644
--- a/lib/irb/input-method.rb
+++ b/lib/irb/input-method.rb
@@ -83,7 +83,15 @@ module IRB
     #
     # See IO#eof? for more information.
     def eof?
-      @stdin.eof?
+      rs, = IO.select([@stdin], [], [], 0.00001)
+      if rs and rs[0]
+        c = @stdin.getc
+        result = c.nil? ? true : false
+        @stdin.ungetc(c) unless c.nil?
+        result
+      else # buffer is empty
+        false
+      end
     end
 
     # Whether this input method is still readable when there is no more data to