From b26dd41dd2dfed7779a45f8731a3012b278bc09d Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Thu, 21 Jul 2022 10:42:57 +0900
Subject: [PATCH 1/2] Install to a temporary directory

---
 Rakefile | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/Rakefile b/Rakefile
index ea66b04..c8b4a52 100644
--- a/Rakefile
+++ b/Rakefile
@@ -43,11 +43,13 @@ task :check do
     gem = "pkg/digest-#{version}#{"-java" if RUBY_ENGINE == "jruby"}.gem"
     File.size?(gem) or abort "gem not built!"
 
-    sh "gem", "install", gem
-
     require_relative "test/lib/envutil"
 
-    _, _, status = EnvUtil.invoke_ruby([], <<~EOS)
+    require 'tmpdir'
+    status = Dir.mktmpdir do |tmpdir|
+      sh "gem", "install", "--install-dir", tmpdir, "--no-document", gem
+
+      _, _, status = EnvUtil.invoke_ruby([{"GEM_HOME"=>tmpdir}], <<~EOS)
       version = #{version.dump}
       gem "digest", version
       loaded_version = Gem.loaded_specs["digest"].version.to_s
@@ -68,7 +70,9 @@ task :check do
       if actual != expected
         abort "no! expected to be \#{expected.dump}!"
       end
-    EOS
+      EOS
+      status
+    end
 
     if status.success?
       puts "check succeeded!"

From 2c5b13cc73a54c5cd3af0616de18626a554a9fee Mon Sep 17 00:00:00 2001
From: Nobuyoshi Nakada <nobu@ruby-lang.org>
Date: Thu, 21 Jul 2022 11:20:22 +0900
Subject: [PATCH 2/2] Check the loaded library path

---
 Rakefile | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Rakefile b/Rakefile
index c8b4a52..0ed3265 100644
--- a/Rakefile
+++ b/Rakefile
@@ -47,6 +47,7 @@ task :check do
 
     require 'tmpdir'
     status = Dir.mktmpdir do |tmpdir|
+      tmpdir = File.realpath(tmpdir)
       sh "gem", "install", "--install-dir", tmpdir, "--no-document", gem
 
       _, _, status = EnvUtil.invoke_ruby([{"GEM_HOME"=>tmpdir}], <<~EOS)
@@ -62,6 +63,13 @@ task :check do
 
       require "digest"
 
+      unless RUBY_ENGINE == "jruby"
+        found = $".select {|path| path.end_with?("/digest.#{RbConfig::CONFIG["DLEXT"]}")}
+        unless found.size == 1 and found.first.start_with?(#{tmpdir.dump})
+          abort "Unexpected digest is loaded: \#{found.inspect}"
+        end
+      end
+
       string = "digest"
       actual = Digest::SHA256.hexdigest(string)
       expected = "0bf474896363505e5ea5e5d6ace8ebfb13a760a409b1fb467d428fc716f9f284"