test: don't use test-unit-rr

Gemfile

@@ -28,5 +28,4 @@ end
 
 group :test do
   gem "test-unit"
-  gem "test-unit-rr"
 end

test/helper.rb

@@ -1,4 +1,4 @@
-# Copyright (C) 2004-2019  Kouhei Sutou <[email protected]>
+# Copyright (C) 2004-2024  Sutou Kouhei <[email protected]>
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,7 +19,6 @@
 require "tmpdir"
 
 require "test-unit"
-require "test/unit/rr"
 
 require "helper/fixture"
 require "helper/parser"

test/test-readme-parser.rb

@@ -1,4 +1,4 @@
-# Copyright (C) 2012-2013  Kouhei Sutou <[email protected]>
+# Copyright (C) 2012-2024  Sutou Kouhei <[email protected]>
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -30,17 +30,20 @@ def setup
 
   private
   def assert_parse(content, extension=nil)
-    readme_path = "README#{extension}"
-    stub(File).read(readme_path) {content}
-    @parser.parse(readme_path)
-    assert_equal({
-                   :title       => @title,
-                   :description => @description,
-                 },
-                 {
-                   :title       => @parser.title,
-                   :description => @parser.description,
-                 })
+    Tempfile.create(["README", extension]) do |readme_file|
+      readme_file.print(content)
+      readme_file.close
+
+      @parser.parse(readme_file.path)
+      assert_equal({
+                     :title       => @title,
+                     :description => @description,
+                   },
+                   {
+                     :title       => @parser.title,
+                     :description => @parser.description,
+                   })
+    end
   end
 
   class TestRD < self