Bring Rails 4.2 (and Ruby 2.4) support back

.github/workflows/test.yml

@@ -70,6 +70,10 @@ jobs:
           - name: "Ruby 2.5 & Rails 5.0"
             ruby-version: "2.5"
             rails-version: "5.0"
+          - name: "Ruby 2.4 & Rails 4.2"
+            ruby-version: "2.4"
+            rails-version: "4.2"
+            bundler_version: 1
     env:
       BUNDLE_GEMFILE: gemfiles/rails${{ matrix.rails-version }}.gemfile
       DISPLAY: ":99.0"
@@ -78,6 +82,8 @@ jobs:
       - uses: ruby/setup-ruby@v1
         with:
           ruby-version: ${{ matrix.ruby-version }}
+          rubygems: ${{ (matrix.ruby_version < '2.6' && 'default') || 'latest' }}
+          bundler: ${{ matrix.bundler_version }}
           bundler-cache: true
       - uses: nanasess/setup-chromedriver@v1
       - name: Test
@@ -102,6 +108,8 @@ jobs:
             rails-version: "5.1"
           - ruby-version: "2.7"
             rails-version: "5.0"
+          - ruby-version: "2.4"
+            rails-version: "4.2"
     steps:
       - uses: actions/checkout@v3
       - name: Test

gemfiles/rails4.2.gemfile

@@ -0,0 +1,26 @@
+# -*- ruby -*-
+#
+# Copyright (C) 2023  Akira Matsuda <[email protected]>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+source "https://rubygems.org/"
+
+gemspec path: ".."
+
+gem "rails", "< 5.0.0"
+gem "capybara", "~> 2.13"
+gem "sqlite3", "~> 1.3.6"
+gem "loofah", "< 2.21.0"

test-unit-rails.gemspec

@@ -40,7 +40,7 @@ Gem::Specification.new do |spec|
   spec.files += Dir.glob("doc/text/**/*.md")
   spec.test_files = Dir.glob("test/**/*.rb")
 
-  spec.add_runtime_dependency("rails", ">= 5.0.0")
+  spec.add_runtime_dependency("rails", ">= 4.2.0")
   spec.add_runtime_dependency("test-unit-activesupport", ">= 1.0.8")
   spec.add_runtime_dependency("test-unit-capybara", ">= 1.0.5")
   spec.add_runtime_dependency("test-unit-rr", ">= 1.0.4")