From 1d9f2a450410e57c5d7fbfe078872a95eb3ec82a Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Thu, 31 Oct 2019 01:09:18 +0900
Subject: [PATCH] [ruby/racc] Show diffs

https://github.com/ruby/racc/commit/0b679e2f69
---
 test/racc/case.rb | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/racc/case.rb b/test/racc/case.rb
index f4240bfd21..d917f3a4e4 100644
--- a/test/racc/case.rb
+++ b/test/racc/case.rb
@@ -90,8 +90,7 @@ module Racc
       actual   = File.read("#{@TAB_DIR}/#{file}")
       result   = (strip_version(expected) == strip_version(actual))
 
-      assert(result, "Output of test/assets/#{file}.y differed from " \
-        "expectation. Try compiling it and diff with test/regress/#{file}.")
+      assert(result, proc {`diff -u #{REGRESS_DIR}/#{file} #{@TAB_DIR}/#{file}`})
     end
 
     def racc(*arg, **opt)