Test with Ruby 4.0

https://www.ruby-lang.org/en/news/2025/12/25/ruby-4-0-0-released/

We need to add `ostruct` as a dev dependency because it doesn't come
as a default gem with Ruby 4.0 anymore.

Author: carlosantoniodasilva

.github/workflows/test.yml

@@ -13,6 +13,7 @@ jobs:
           - gemfiles/Gemfile-rails-7-2
           - gemfiles/Gemfile-rails-8-0
         ruby:
+          - '4.0'
           - '3.4'
           - '3.3'
           - '3.2'

CHANGELOG.md

@@ -24,7 +24,7 @@
 * enhancements
   * Add Rails 8 support.
     - Routes are lazy-loaded by default in test and development environments now so Devise loads them before `Devise.mappings` call. [#5728](https://github.com/heartcombo/devise/pull/5728)
-  * Add Ruby 3.4 support.
+  * Add Ruby 3.4 and 4.0 support.
   * Reenable Mongoid test suite across all Rails 7+ versions, to ensure we continue supporting it. Changes to dirty tracking to support Mongoid 8.0+. [#5568](https://github.com/heartcombo/devise/pull/5568)
   * Password length validator is changed from
 

Gemfile

@@ -21,6 +21,7 @@ group :test do
   gem "rexml"
   gem "timecop"
   gem "webrat"
+  gem "ostruct"
 end
 
 platforms :ruby do

Gemfile.lock

@@ -188,6 +188,7 @@ GEM
       ruby-openid (~> 2.1, >= 2.1.8)
       version_gem (~> 1.1, >= 1.1.8)
     orm_adapter (0.5.0)
+    ostruct (0.6.3)
     pp (0.6.3)
       prettyprint
     prettyprint (0.2.0)
@@ -297,6 +298,7 @@ DEPENDENCIES
   omniauth-facebook
   omniauth-oauth2
   omniauth-openid
+  ostruct
   rails (~> 8.1.0)
   rails-controller-testing
   rdoc
@@ -307,4 +309,4 @@ DEPENDENCIES
   webrat
 
 BUNDLED WITH
-   2.6.9
+   4.0.3

gemfiles/Gemfile-rails-7-0

@@ -19,6 +19,7 @@ group :test do
   gem "webrat", "0.7.3", require: false
   gem "mocha", "~> 2.1", require: false
   gem "minitest", "< 6"
+  gem "ostruct"
 end
 
 platforms :ruby do

gemfiles/Gemfile-rails-7-1

@@ -19,6 +19,7 @@ group :test do
   gem "webrat"
   gem "mocha", "~> 2.1", require: false
   gem "minitest", "< 6"
+  gem "ostruct"
 end
 
 platforms :ruby do

gemfiles/Gemfile-rails-7-2

@@ -20,6 +20,7 @@ group :test do
   gem "webrat", require: false
   gem "mocha", "~> 2.1", require: false
   gem "minitest", "< 6"
+  gem "ostruct"
 end
 
 platforms :ruby do

gemfiles/Gemfile-rails-8-0

@@ -19,6 +19,7 @@ group :test do
   gem 'webrat'
   gem "mocha", "~> 2.1", require: false
   gem "minitest", "< 6"
+  gem "ostruct"
 end
 
 platforms :ruby do

gemfiles/Gemfile-rails-main

@@ -19,6 +19,7 @@ group :test do
   gem "webrat", "0.7.3", require: false
   gem "mocha", "~> 2.1", require: false
   gem "minitest", "< 6"
+  gem "ostruct"
 end
 
 platforms :ruby do