Reorganize test matrix & use latest bundler

* Rails and Ruby versions follow the most recent to oldest, except for
  Rails main, so we can keep the Gemfile the first one.
* Excluding specific matrix combinations based on the Gemfile first,
  Ruby version next, and keep the same order (most recent -> oldest)
* Quote all Ruby versions to keep things consistent. It's required for
  the '3.0' version to avoid the float issue where it'd use the latest
  3.x instead.
* Test Rails 6.1 with Ruby 3.1, as Rails test suite supports it.

Also update Changelog with the 3.1 Ruby support addition.

.github/workflows/test.yml

@@ -7,35 +7,33 @@ jobs:
       matrix:
         gemfile:
           - Gemfile
-          - gemfiles/Gemfile-rails-5-2
-          - gemfiles/Gemfile-rails-6-0
-          - gemfiles/Gemfile-rails-6-1
           - gemfiles/Gemfile-rails-main
+          - gemfiles/Gemfile-rails-6-1
+          - gemfiles/Gemfile-rails-6-0
+          - gemfiles/Gemfile-rails-5-2
         ruby:
-          - 2.5
-          - 2.6
-          - 2.7
+          - '3.1'
           - '3.0'
-          - 3.1
+          - '2.7'
+          - '2.6'
+          - '2.5'
         exclude:
-          - ruby: 2.5
-            gemfile: gemfiles/Gemfile-rails-main
-          - ruby: 2.6
-            gemfile: gemfiles/Gemfile-rails-main
-          - ruby: 2.5
-            gemfile: Gemfile
-          - ruby: 2.6
-            gemfile: Gemfile
-          - ruby: 2.7
-            gemfile: gemfiles/Gemfile-rails-5-2
-          - ruby: 3.0
-            gemfile: gemfiles/Gemfile-rails-5-2
-          - ruby: 3.1
-            gemfile: gemfiles/Gemfile-rails-5-2
-          - ruby: 3.1
-            gemfile: gemfiles/Gemfile-rails-6-0
-          - ruby: 3.1
-            gemfile: gemfiles/Gemfile-rails-6-1
+          - gemfile: Gemfile
+            ruby: '2.6'
+          - gemfile: Gemfile
+            ruby: '2.5'
+          - gemfile: gemfiles/Gemfile-rails-main
+            ruby: '2.6'
+          - gemfile: gemfiles/Gemfile-rails-main
+            ruby: '2.5'
+          - gemfile: gemfiles/Gemfile-rails-6-0
+            ruby: '3.1'
+          - gemfile: gemfiles/Gemfile-rails-5-2
+            ruby: '3.1'
+          - gemfile: gemfiles/Gemfile-rails-5-2
+            ruby: '3.0'
+          - gemfile: gemfiles/Gemfile-rails-5-2
+            ruby: '2.7'
     runs-on: ubuntu-latest
     env: # $BUNDLE_GEMFILE must be set at the job level, so it is set for all steps
       BUNDLE_GEMFILE: ${{ matrix.gemfile }}

CHANGELOG.md

@@ -1,6 +1,6 @@
 ## Unreleased
 
-* Add support for Rails 7.0 (no changes required)
+* Add support for Rails 7.0 and Ruby 3.1 (no changes required)
 
 ## 5.1.0
 

Gemfile.lock

@@ -90,4 +90,4 @@ DEPENDENCIES
   simple_form!
 
 BUNDLED WITH
-   2.1.4
+   2.3.8