CI: Regularly test with Rails' main branch

.github/workflows/rails-main-branch-test.yml

@@ -0,0 +1,18 @@
+---
+name: Tests on the "main" branch of Rails
+
+on:
+  schedule:
+    - cron: '15 8 * * MON'
+  workflow_dispatch:
+
+jobs:
+  test:
+    name: ActiveRecord main / Ruby 3.3
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: docker-compose run test
+        env:
+          RUBY_VERSION: "3.3"
+          AR_VERSION: "main"

.github/workflows/test.yml

@@ -20,7 +20,7 @@ jobs:
         include:
           - {activerecord-version: "5.2", ruby-version: "2.7"}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: docker-compose run test
         env:
           RUBY_VERSION: ${{ matrix.ruby-version }}

gemfiles/main.gemfile

@@ -0,0 +1,11 @@
+source "https://rubygems.org"
+
+gemspec path: ".."
+
+gem "activesupport", github: "rails/rails"
+gem "activemodel", github: "rails/rails"
+gem "activerecord", github: "rails/rails"
+gem "sqlite3", ">= 1.4"
+gem "mysql2", "~> 0.5"
+gem "pg", "~> 1.1"
+gem "trilogy", "~> 2.7"