Get Ruby 3.1 in CI and passing for Rails 6.1

Author: petergoldstein

.github/workflows/ci.yml

@@ -17,6 +17,10 @@ jobs:
       matrix:
        include:
          # Edge Rails (7.1) builds >= 2.7
+         - ruby: '3.1'
+           allow_failure: true
+           env:
+             RAILS_VERSION: 'main'
          - ruby: '3.0'
            allow_failure: true
            env:
@@ -41,6 +45,9 @@ jobs:
              RAILS_VERSION: '~> 7.0.0'
 
          # Rails 6.1 builds >= 2.5
+         - ruby: '3.1'
+           env:
+             RAILS_VERSION: '~> 6.1.0'
          - ruby: '3.0'
            env:
              RAILS_VERSION: '~> 6.1.0'

Gemfile-rails-dependencies

@@ -25,4 +25,15 @@ else
   gem "puma"
   gem 'activerecord-jdbcsqlite3-adapter', platforms: [:jruby]
   gem 'selenium-webdriver', require: false
+
+  # This is required for Ruby 3.1 and Rails 6.1.x as of time
+  # of writing, because in Ruby 3.1 these gems are no longer
+  # automatically included.  This issue was fixed on the Rails
+  # side in Rails 7.0.1, but is not yet fixed in the Rails 6.1.x
+  # branch.  Discussion can be found here - https://github.com/mikel/mail/pull/1439
+  if RUBY_VERSION >= '3.1' && version.split(' ').last < '7.0'
+    gem 'net-smtp', require: false
+    gem 'net-imap', require: false
+    gem 'net-pop', require: false
+  end
 end