From b89f6ac843d9abbe8488bd329e0ff0cccf5caaa3 Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Sun, 30 Jun 2019 21:12:15 +0900
Subject: [PATCH] Check for the privileges by the current process groups

Group membership of login user is not activated until login after
adding to the group.
---
 test/dtrace/helper.rb | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/test/dtrace/helper.rb b/test/dtrace/helper.rb
index 7b382e86ca..2243d15c95 100644
--- a/test/dtrace/helper.rb
+++ b/test/dtrace/helper.rb
@@ -19,9 +19,7 @@ if RUBY_PLATFORM =~ /linux/
   impl = :stap
   begin
     require 'etc'
-    login = Etc.getlogin
-    ok = Etc.getgrnam('stapusr').mem.include?(login) &&
-           Etc.getgrnam('stapdev').mem.include?(login)
+    ok = (%w[stapusr stapdev].map {|g|Etc.getgrnam(g).gid} & Process.groups).size == 2
   rescue LoadError, ArgumentError
   end unless ok
 end