From 8ee51788fd57c70ed9b2366fee63c9a5c7ee8841 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 10:24:39 +0200
Subject: [PATCH 1/9] Support Active Admin 4

Active Admin 4 removed Filters::ViewHelper and Filters::ActiveSidebar, so
those prepends now run only on v3. On v4 the gem hooks FormHelper and the
active_search section's condition, and sends warnings to :alert, the only
warning-like key the v4 layout renders.

Co-Authored-By: Clanker
---
 active_admin_filter_extensions.gemspec        |  2 +-
 lib/active_admin_filter_extensions.rb         | 21 +++++++++++--
 .../filters_form.rb                           | 31 ++++++++++++++++++-
 .../policies.rb                               |  6 ++--
 4 files changed, 52 insertions(+), 8 deletions(-)

diff --git a/active_admin_filter_extensions.gemspec b/active_admin_filter_extensions.gemspec
index 5793b91..2e9843e 100644
--- a/active_admin_filter_extensions.gemspec
+++ b/active_admin_filter_extensions.gemspec
@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
                   "the URL."
 
   s.required_ruby_version = ">= 3.3"
-  s.add_dependency "activeadmin", ">= 3.5", "< 4"
+  s.add_dependency "activeadmin", ">= 3.5", "< 5"
 
   s.files         = `git ls-files`.split("\n")
   s.require_paths = ["lib"]
diff --git a/lib/active_admin_filter_extensions.rb b/lib/active_admin_filter_extensions.rb
index cfc4871..bb6638b 100644
--- a/lib/active_admin_filter_extensions.rb
+++ b/lib/active_admin_filter_extensions.rb
@@ -32,6 +32,16 @@ class << self
     def notice_flash_key
       @notice_flash_key ||= :notice
     end
+
+    # Active Admin 4 moved the filters form helper and the Current Filters section.
+    def aa_v4?
+      Gem::Version.new(ActiveAdmin::VERSION) >= Gem::Version.new("4.0.0.beta1")
+    end
+
+    # Active Admin 4's layout renders only the :error, :alert and :notice flash keys.
+    def warning_flash_key
+      aa_v4? ? :alert : :warning
+    end
   end
 end
 
@@ -49,7 +59,6 @@ def notice_flash_key
   ActiveAdmin::ResourceController.helper_method :filtering_params, :applied_filter_params,
                                                 :filter_default_values, :visible_filters
 
-  ActiveAdmin::Resource.prepend ActiveAdminFilterExtensions::ResourceExtension
   ActiveAdmin::ResourceDSL.include ActiveAdminFilterExtensions::Policies::ResourcePolicyDSL
   ActiveAdmin::Resource.include ActiveAdminFilterExtensions::Policies::ResourcePolicySettings
   ActiveAdmin::ResourceDSL.include ActiveAdminFilterExtensions::Notice
@@ -58,6 +67,12 @@ def notice_flash_key
   # decision - and therefore the URL - is computed from.
   ActiveAdmin::ResourceController.include ActiveAdminFilterExtensions::Policies::Controller
   ActiveAdmin::ResourceController.include ActiveAdminFilterExtensions::Redirect
-  ActiveAdmin::Filters::ViewHelper.prepend ActiveAdminFilterExtensions::ViewHelper
-  ActiveAdmin::Filters::ActiveSidebar.prepend ActiveAdminFilterExtensions::ActiveSidebar
+  if ActiveAdminFilterExtensions.aa_v4?
+    ActiveAdmin::Resource.prepend ActiveAdminFilterExtensions::ResourceExtensionV4
+    ActiveAdmin::FormHelper.prepend ActiveAdminFilterExtensions::ViewHelper
+  else
+    ActiveAdmin::Resource.prepend ActiveAdminFilterExtensions::ResourceExtension
+    ActiveAdmin::Filters::ViewHelper.prepend ActiveAdminFilterExtensions::ViewHelper
+    ActiveAdmin::Filters::ActiveSidebar.prepend ActiveAdminFilterExtensions::ActiveSidebar
+  end
 end
diff --git a/lib/active_admin_filter_extensions/filters_form.rb b/lib/active_admin_filter_extensions/filters_form.rb
index a061750..231240c 100644
--- a/lib/active_admin_filter_extensions/filters_form.rb
+++ b/lib/active_admin_filter_extensions/filters_form.rb
@@ -1,6 +1,9 @@
 # frozen_string_literal: true
 
 module ActiveAdminFilterExtensions
+  # Stable hooks for page objects, so specs need not select on Active Admin's CSS classes.
+  FORM_OPTIONS = { html: { "data-filter-extensions-form" => "" } }.freeze
+
   # The filters sidebar hands the form the filters that `:if` and `:unless` allow, so the same
   # set is rendered and consulted for defaults, and the conditions are resolved once.
   module ResourceExtension
@@ -11,11 +14,37 @@ def filters_sidebar_section
         # Passed positionally rather than splatted: the section is shown when the resource has
         # any filter at all, and `**{}` would drop the argument entirely once `:if` and
         # `:unless` have denied every one of them.
-        active_admin_filters_form_for assigns[:search], visible_filters
+        active_admin_filters_form_for assigns[:search], visible_filters, FORM_OPTIONS
       end
     end
   end
 
+  # Active Admin 4's sidebar: the section title is rendered inside the block, as
+  # `h3.filters-form-title`, and the Current Filters panel is a section of its own.
+  module ResourceExtensionV4
+    private
+
+    def filters_sidebar_section
+      name = :filters
+      ActiveAdmin::SidebarSection.new name, only: :index, if: -> { active_admin_config.filters.any? } do
+        h3 I18n.t("active_admin.sidebars.#{name}", default: name.to_s.titlecase),
+           class: "filters-form-title", "data-filter-extensions-title" => ""
+        active_admin_filters_form_for assigns[:search], visible_filters, FORM_OPTIONS
+      end
+    end
+
+    # Gated on `params[:q]` like ActiveSidebar below; only its condition is widened.
+    def active_search_sidebar_section
+      section = super
+      shown = section.options[:if]
+      section.options[:if] = lambda {
+        instance_exec(&shown) ||
+          (active_admin_config.current_filters_enabled? && filter_default_values.present?)
+      }
+      section
+    end
+  end
+
   # The form renders what it is handed: `:if` and `:unless` were already resolved by
   # #visible_filters, and the policy keys - merged flat into these options by
   # #merge_filter_extensions - are not Formtastic's business. required: in particular is also a
diff --git a/lib/active_admin_filter_extensions/policies.rb b/lib/active_admin_filter_extensions/policies.rb
index 1164b15..8bb8678 100644
--- a/lib/active_admin_filter_extensions/policies.rb
+++ b/lib/active_admin_filter_extensions/policies.rb
@@ -140,7 +140,7 @@ def enforce_require_any_filter
         # Active Admin reads a q-less index as "this table has no rows" and renders the blank
         # slate, Create link and all; a present-but-empty q renders an empty result instead.
         params[:q] ||= {}
-        flash.now[:warning] =
+        flash.now[ActiveAdminFilterExtensions.warning_flash_key] =
           notice.is_a?(String) ? notice : I18n.t(notice, scope: :active_admin_filter_extensions,
                                                  default: :require_any_filter)
       end
@@ -181,8 +181,8 @@ def enforce_with_groups(q)
           filter_policy_errors << keys
           filter_policy_reset_keys.concat(keys)
           names = keys.map { |k| strip_ransack_predicate(k).humanize }.uniq.join(" and ")
-          flash.now[:warning] = I18n.t(:given_together, scope: :active_admin_filter_extensions,
-                                       filters: names)
+          flash.now[ActiveAdminFilterExtensions.warning_flash_key] =
+            I18n.t(:given_together, scope: :active_admin_filter_extensions, filters: names)
           present.flatten.each { |key| q.delete(key) }
         end
       end

From e8349a6cb9ed09dd8f437a7ab24ca5c7522d17a4 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 10:24:50 +0200
Subject: [PATCH 2/9] Run the suite on Active Admin 4 too

Co-Authored-By: Clanker
---
 .github/workflows/ci.yml         |  2 +-
 Gemfile                          | 14 ++++++++--
 spec/integration/sidebar_spec.rb | 47 ++++++++++++++++++++++++++++++++
 spec/integration/with_spec.rb    |  2 +-
 spec/rails_helper.rb             |  3 +-
 spec/support/rails_template.rb   | 10 +++++++
 tasks/test.rake                  |  8 ++++--
 7 files changed, 77 insertions(+), 9 deletions(-)
 create mode 100644 spec/integration/sidebar_spec.rb

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 0410c38..868676a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,7 +19,7 @@ jobs:
         # on 2026-03-31, so the floor there is 3.3 (security-only until 2027-03-31).
         ruby: ['3.3', '3.4', '4.0']
         rails: ['8.0.0', '8.1.0']
-        activeadmin: ['3.5.0']
+        activeadmin: ['3.5.0', '4.0.0.beta23']
     env:
       RAILS: ${{ matrix.rails }}
       AA: ${{ matrix.activeadmin }}
diff --git a/Gemfile b/Gemfile
index 4d98681..30f5a39 100644
--- a/Gemfile
+++ b/Gemfile
@@ -8,9 +8,17 @@ default_rails_version = "8.0.0"
 default_activeadmin_version = "3.5.0"
 
 gem "rails", "~> #{ENV['RAILS'] || default_rails_version}"
-gem "activeadmin", "~> #{ENV['AA'] || default_activeadmin_version}"
-gem "sprockets-rails"
-gem "sass-rails"
+activeadmin_version = ENV["AA"] || default_activeadmin_version
+gem "activeadmin", "~> #{activeadmin_version}"
+# Active Admin 4 serves its assets through propshaft and an import map, Active Admin 3 through
+# Sprockets and Sass.
+if Gem::Version.new(activeadmin_version) >= Gem::Version.new("4.0.0.beta1")
+  gem "importmap-rails"
+  gem "propshaft"
+else
+  gem "sprockets-rails"
+  gem "sass-rails"
+end
 
 group :test do
   gem "capybara"
diff --git a/spec/integration/sidebar_spec.rb b/spec/integration/sidebar_spec.rb
new file mode 100644
index 0000000..ada6a6d
--- /dev/null
+++ b/spec/integration/sidebar_spec.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+# The sidebar markup moved in Active Admin 4: the Current Filters section has its own id and the
+# filters section renders its title inside the block.
+RSpec.describe "the filters sidebar", type: :feature do
+  let(:aa_v4) { ActiveAdminFilterExtensions.aa_v4? }
+  let(:current_filters) { aa_v4 ? "#active_search_sidebar_section" : "#search_status_sidebar_section" }
+
+  it "marks the filters form with a data hook" do
+    visit "/admin/string_posts"
+
+    expect(page).to have_css("#filters_sidebar_section form[data-filter-extensions-form]")
+  end
+
+  it "shows the Current Filters panel when only defaults apply" do
+    visit "/admin/string_posts"
+
+    expect(page).to have_css(current_filters, text: "keep")
+  end
+
+  it "hides the Current Filters panel when nothing is filtered" do
+    visit "/admin/no_defaults_posts"
+
+    expect(page).to have_css("#filters_sidebar_section")
+    expect(page).to have_no_css(current_filters)
+  end
+
+  it "keeps the Current Filters panel for a filter from the request" do
+    visit "/admin/no_defaults_posts?q%5Btitle_cont%5D=keep"
+
+    expect(page).to have_css(current_filters, text: "keep")
+  end
+
+  it "renders the filters title once" do
+    visit "/admin/string_posts"
+
+    if aa_v4
+      expect(page).to have_css("#filters_sidebar_section h3.filters-form-title[data-filter-extensions-title]",
+                               count: 1, text: "Filters")
+    else
+      expect(page).to have_no_css("#filters_sidebar_section .filters-form-title")
+      expect(page).to have_css("#filters_sidebar_section h3", count: 1, text: "Filters")
+    end
+  end
+end
diff --git a/spec/integration/with_spec.rb b/spec/integration/with_spec.rb
index 1c05618..92d7249 100644
--- a/spec/integration/with_spec.rb
+++ b/spec/integration/with_spec.rb
@@ -48,7 +48,7 @@ def query_of(url)
     # PairedPost declares with: on both members - the two declarations are one group.
     visit "/admin/paired_posts?q%5Bstatus_eq%5D=draft"
 
-    expect(page).to have_css(".flash_warning", count: 1)
+    expect(page).to have_css(".flash_#{ActiveAdminFilterExtensions.warning_flash_key}", count: 1)
   end
 
   it "does not count a blank-array partner as answered" do
diff --git a/spec/rails_helper.rb b/spec/rails_helper.rb
index 8195e04..9d6e3bf 100644
--- a/spec/rails_helper.rb
+++ b/spec/rails_helper.rb
@@ -12,7 +12,8 @@
 ENV["RAILS_ENV"] = "test"
 require "rails"
 ENV["RAILS"] = Rails.version
-ENV["RAILS_ROOT"] = File.expand_path("rails/rails-#{ENV['RAILS']}", __dir__)
+aa_major = Gem.loaded_specs["activeadmin"].version.segments.first
+ENV["RAILS_ROOT"] = File.expand_path("rails/rails-#{ENV['RAILS']}-aa#{aa_major}", __dir__)
 
 unless File.exist?(ENV["RAILS_ROOT"])
   # A generation that dies midway leaves a partial app the File.exist? guard would then skip
diff --git a/spec/support/rails_template.rb b/spec/support/rails_template.rb
index 01ffe01..3cba5d5 100644
--- a/spec/support/rails_template.rb
+++ b/spec/support/rails_template.rb
@@ -629,6 +629,16 @@ def filter_defaults_apply?
     end
   RUBY
 
+# Active Admin 4's flash partial renders only :error, :alert and :notice, with no class per key.
+# An app that moves the notice to a key of its own renders that key itself, as this one does.
+if Gem.loaded_specs["activeadmin"].version >= Gem::Version.new("4.0.0.beta1")
+  file "app/views/active_admin/_flash_messages.html.erb", <<~ERB
+    <% flash_messages.each do |type, message| %>
+      <div class="flash flash_<%= type %>"><%= message %></div>
+    <% end %>
+  ERB
+end
+
 run "rm -rf test"
 route "root to: 'admin/dashboard#index'"
 rake "db:migrate"
diff --git a/tasks/test.rake b/tasks/test.rake
index 76bd3de..b5ed0b0 100644
--- a/tasks/test.rake
+++ b/tasks/test.rake
@@ -4,8 +4,8 @@ desc "Creates a test rails app for the specs to run against"
 task :setup do
   require "rails/version"
 
-  # The template throws the generated Gemfile away, so the app runs under this gem's sprockets
-  # bundle with no importmap-rails. Without --skip-javascript, Rails 8.1 writes
+  # The template throws the generated Gemfile away, so the app runs under this gem's bundle,
+  # which has no importmap-rails on Active Admin 3. Without --skip-javascript, Rails 8.1 writes
   # `stale_when_importmap_changes` into ApplicationController and booting it raises NameError.
   args = %w[
     --skip-spring
@@ -16,7 +16,9 @@ task :setup do
     -m spec/support/rails_template.rb
   ].join(" ")
 
-  app_dir = "spec/rails/rails-#{Rails::VERSION::STRING}"
+  # One app per Active Admin major: its installer writes different assets and initializers.
+  aa_major = Gem.loaded_specs["activeadmin"].version.segments.first
+  app_dir = "spec/rails/rails-#{Rails::VERSION::STRING}-aa#{aa_major}"
   # From scratch, always: `rails new` git-inits the app, so a nested repo survives
   # `git clean -fdx` and the generator would then write into the surviving tree - leaving a
   # stale resource behind a freshly stamped digest, which is a green the stamp exists to deny.

From 89ba83af1208c88dc300cb3aa36e48cfcd743168 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 10:24:50 +0200
Subject: [PATCH 3/9] Document Active Admin 4 support

Co-Authored-By: Clanker
---
 README.md | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 828c455..3cc7e10 100644
--- a/README.md
+++ b/README.md
@@ -182,6 +182,11 @@ writes action results to `:notice`, and on a shared key the arriving message win
 action's result would silence the notice. The key is read when the notice is written and
 `flash_key:` on the resource still beats it.
 
+On Active Admin 4 the stock layout renders only the `:error`, `:alert` and `:notice` flash
+keys, so a key of your own needs an override of `app/views/active_admin/_flash_messages.html.erb`
+that renders it. The `with:` and `require_any_filter` warnings go to `:alert` there, and to
+`:warning` on Active Admin 3.
+
 ## Required filters: the mandatory window
 
 Some tables must never be queried without a bound - a log partitioned by date, a CDR table
@@ -363,7 +368,16 @@ Four prints in small type:
   another predicate - wants `applied_filter_params`: the same values as an indifferent copy,
   safe to read by symbol and to mutate. Both are helpers, so a view can call them too.
 
-Tested against Active Admin 3.5 on Rails 8.0 and 8.1, under Ruby 3.3, 3.4 and 4.0.
+## Active Admin 4
+
+The gem works on Active Admin 3.5 and 4 from the same release; it ships no JavaScript or CSS.
+On Active Admin 4 the filters section keeps Active Admin's own `h3.filters-form-title`, and
+the Current Filters section (`#active_search_sidebar_section`) also shows when only defaults
+apply. Page objects can select the filters form by `[data-filter-extensions-form]` and, on
+Active Admin 4, its title by `[data-filter-extensions-title]`.
+
+Tested against Active Admin 3.5 and 4.0.0.beta23 on Rails 8.0 and 8.1, under Ruby 3.3, 3.4
+and 4.0.
 
 ## License
 

From 5d3b8c56d2764b4b5f7c4bff7cd1823fa80973ac Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 13:59:42 +0200
Subject: [PATCH 4/9] Pass Active Admin 4's auth object to Ransack

Active Admin 4 hands Ransack its authorization adapter, so a model's
ransackable_attributes can depend on the admin. Both of this gem's Ransack
calls dropped it, which could leave a permitted filter unapplied or fail
key derivation for a defaulted filter.

Co-Authored-By: Clanker
---
 .../data_access.rb                            |  5 +----
 .../search_keys.rb                            |  9 +++++++-
 spec/integration/ransack_auth_object_spec.rb  | 21 +++++++++++++++++++
 spec/spec_helper.rb                           |  3 +++
 4 files changed, 33 insertions(+), 5 deletions(-)
 create mode 100644 spec/integration/ransack_auth_object_spec.rb

diff --git a/lib/active_admin_filter_extensions/data_access.rb b/lib/active_admin_filter_extensions/data_access.rb
index 6d42a7c..feb3839 100644
--- a/lib/active_admin_filter_extensions/data_access.rb
+++ b/lib/active_admin_filter_extensions/data_access.rb
@@ -4,14 +4,11 @@ module ActiveAdminFilterExtensions
   # The single method this gem replaces: Active Admin searches the collection on `params[:q]`
   # read directly, and it searches #filtering_params instead. Everything that method means is
   # in FilterDefaults.
-  #
-  # The Ransack call is the Active Admin 3 one, which this gem targets: Active Admin 4 passes
-  # `auth_object: active_admin_authorization` there as well.
   module DataAccess
     protected
 
     def apply_filtering(chain)
-      @search = chain.ransack(filtering_params)
+      @search = chain.ransack(filtering_params, **filter_ransack_options)
       # An :empty policy keeps the request intact - the form still shows what the admin
       # typed - and blanks the collection instead.
       return @search.result.none if filter_policy_render_empty?
diff --git a/lib/active_admin_filter_extensions/search_keys.rb b/lib/active_admin_filter_extensions/search_keys.rb
index 1ee1210..0659992 100644
--- a/lib/active_admin_filter_extensions/search_keys.rb
+++ b/lib/active_admin_filter_extensions/search_keys.rb
@@ -60,10 +60,17 @@ def filter_input_options(options, builder)
     # time it is called, and every defaulted filter would pay for another one.
     def filter_input_builder
       @filter_input_builder ||= ::ActiveAdmin::Filters::FormBuilder.new(
-        :q, active_admin_config.resource_class.ransack({}), view_context, {}
+        :q, active_admin_config.resource_class.ransack({}, **filter_ransack_options), view_context, {}
       )
     end
 
+    # What Active Admin passes to Ransack next to the search: version 4 hands over its
+    # authorization adapter, so a model's `ransackable_attributes(auth_object)` can depend on
+    # the admin; version 3 passes nothing.
+    def filter_ransack_options
+      ActiveAdminFilterExtensions.aa_v4? ? { auth_object: active_admin_authorization } : {}
+    end
+
     def raise_filter_default_error(attribute, message)
       raise ArgumentError, "filter :#{attribute} declares a `default:` but #{message}"
     end
diff --git a/spec/integration/ransack_auth_object_spec.rb b/spec/integration/ransack_auth_object_spec.rb
new file mode 100644
index 0000000..38afc64
--- /dev/null
+++ b/spec/integration/ransack_auth_object_spec.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+# Active Admin 4 passes its authorization adapter to Ransack, so a model's allowlist can depend
+# on the admin. The gem's own search and its search-key derivation must pass it on as well.
+RSpec.describe "the Ransack auth object", type: :feature do
+  it "reaches the model's allowlist from every search the index builds" do
+    seen = []
+    allow(Post).to receive(:ransackable_attributes).and_wrap_original do |original, auth_object = nil|
+      seen << auth_object
+      original.call(auth_object)
+    end
+
+    visit "/admin/string_posts"
+
+    expected = ActiveAdminFilterExtensions.aa_v4? ? ActiveAdmin::AuthorizationAdapter : NilClass
+    expect(seen).not_to be_empty
+    expect(seen).to all(be_a(expected))
+  end
+end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index fdea2db..b5452ad 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -55,6 +55,9 @@ def filter_search_keys(attribute, _options)
     @search_keys.fetch(attribute) { [attribute.to_s] }
   end
 
+  # The real one asks Active Admin's version, which this suite does not load.
+  def filter_ransack_options = {}
+
   prepend ActiveAdminFilterExtensions::DataAccess
   include ActiveAdminFilterExtensions::Policies::Controller
   include ActiveAdminFilterExtensions::FilterOptions

From 16a092e13c010090a6670d3ba7543adb4c4f4703 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 13:59:42 +0200
Subject: [PATCH 5/9] Document running the suite on Active Admin 4

Co-Authored-By: Clanker
---
 README.md | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/README.md b/README.md
index 3cc7e10..06c3068 100644
--- a/README.md
+++ b/README.md
@@ -379,6 +379,14 @@ Active Admin 4, its title by `[data-filter-extensions-title]`.
 Tested against Active Admin 3.5 and 4.0.0.beta23 on Rails 8.0 and 8.1, under Ruby 3.3, 3.4
 and 4.0.
 
+The suite runs on Active Admin 3.5 by default. The `AA` and `RAILS` variables pick other
+versions; `Gemfile.lock` is not committed, so re-resolve the bundle when switching:
+
+```sh
+AA=4.0.0.beta23 bundle update activeadmin
+AA=4.0.0.beta23 bundle exec rake spec
+```
+
 ## License
 
 MIT

From ce78c837ec8c86d001c1ae918584a08b83fe6bd5 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 14:06:30 +0200
Subject: [PATCH 6/9] Exclude ActiveAdmin 5 prereleases

RubyGems treats 5.0.0.beta1 as satisfying "< 5".

Co-Authored-By: Clanker
---
 active_admin_filter_extensions.gemspec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/active_admin_filter_extensions.gemspec b/active_admin_filter_extensions.gemspec
index 2e9843e..bbe749e 100644
--- a/active_admin_filter_extensions.gemspec
+++ b/active_admin_filter_extensions.gemspec
@@ -16,7 +16,7 @@ Gem::Specification.new do |s|
                   "the URL."
 
   s.required_ruby_version = ">= 3.3"
-  s.add_dependency "activeadmin", ">= 3.5", "< 5"
+  s.add_dependency "activeadmin", ">= 3.5", "< 5.0.0.a"
 
   s.files         = `git ls-files`.split("\n")
   s.require_paths = ["lib"]

From 99e85bb9454d6e30481531ff3d414796eb94023e Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 14:16:45 +0200
Subject: [PATCH 7/9] Let an arriving alert win over the filter warnings

On Active Admin 4 the warnings share :alert with the app's own messages, so an action's alert on the redirect was overwritten.

Co-Authored-By: Clanker
---
 README.md                                      |  4 +++-
 lib/active_admin_filter_extensions/policies.rb | 17 ++++++++++++-----
 spec/integration/require_any_filter_spec.rb    |  8 ++++++++
 spec/support/rails_template.rb                 |  6 ++++++
 4 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/README.md b/README.md
index 06c3068..744264c 100644
--- a/README.md
+++ b/README.md
@@ -185,7 +185,9 @@ action's result would silence the notice. The key is read when the notice is wri
 On Active Admin 4 the stock layout renders only the `:error`, `:alert` and `:notice` flash
 keys, so a key of your own needs an override of `app/views/active_admin/_flash_messages.html.erb`
 that renders it. The `with:` and `require_any_filter` warnings go to `:alert` there, and to
-`:warning` on Active Admin 3.
+`:warning` on Active Admin 3. An `:alert` that arrived with the request wins over the warning.
+[activeadmin/activeadmin#9161](https://github.com/activeadmin/activeadmin/pull/9161) makes the
+layout render every key; until a release ships it, the override is still needed.
 
 ## Required filters: the mandatory window
 
diff --git a/lib/active_admin_filter_extensions/policies.rb b/lib/active_admin_filter_extensions/policies.rb
index 8bb8678..7afc577 100644
--- a/lib/active_admin_filter_extensions/policies.rb
+++ b/lib/active_admin_filter_extensions/policies.rb
@@ -140,9 +140,10 @@ def enforce_require_any_filter
         # Active Admin reads a q-less index as "this table has no rows" and renders the blank
         # slate, Create link and all; a present-but-empty q renders an empty result instead.
         params[:q] ||= {}
-        flash.now[ActiveAdminFilterExtensions.warning_flash_key] =
-          notice.is_a?(String) ? notice : I18n.t(notice, scope: :active_admin_filter_extensions,
-                                                 default: :require_any_filter)
+        unless notice.is_a?(String)
+          notice = I18n.t(notice, scope: :active_admin_filter_extensions, default: :require_any_filter)
+        end
+        flash_filter_warning(notice)
       end
 
       # Ransack silently ignores a condition nobody declared - junk, a stale bookmark after
@@ -169,6 +170,13 @@ def any_declared_filter_answered?
         end
       end
 
+      # On Active Admin 4 the warning shares :alert with the app's own messages. A message that
+      # arrived with the request wins, as it does for the notice.
+      def flash_filter_warning(message)
+        key = ActiveAdminFilterExtensions.warning_flash_key
+        flash.now[key] = message if flash[key].blank?
+      end
+
       def enforce_with_groups(q)
         # Membership is judged on the normalized request: a blank-array partner would pass a
         # raw present? check while Ransack drops it - half the group executing silently.
@@ -181,8 +189,7 @@ def enforce_with_groups(q)
           filter_policy_errors << keys
           filter_policy_reset_keys.concat(keys)
           names = keys.map { |k| strip_ransack_predicate(k).humanize }.uniq.join(" and ")
-          flash.now[ActiveAdminFilterExtensions.warning_flash_key] =
-            I18n.t(:given_together, scope: :active_admin_filter_extensions, filters: names)
+          flash_filter_warning(I18n.t(:given_together, scope: :active_admin_filter_extensions, filters: names))
           present.flatten.each { |key| q.delete(key) }
         end
       end
diff --git a/spec/integration/require_any_filter_spec.rb b/spec/integration/require_any_filter_spec.rb
index 1b194ac..3e32d8c 100644
--- a/spec/integration/require_any_filter_spec.rb
+++ b/spec/integration/require_any_filter_spec.rb
@@ -31,6 +31,14 @@
     expect(page).to have_no_link("Create one")
   end
 
+  it "leaves an alert that arrived with the request in place" do
+    # On Active Admin 4 the warning and an action's alert share the :alert key.
+    visit "/admin/picky_posts/poke"
+
+    expect(page).to have_content("poked")
+    expect(page).to have_no_content("keep me")
+  end
+
   it "answers once asked" do
     visit "/admin/picky_posts?q%5Btitle_cont%5D=keep"
 
diff --git a/spec/support/rails_template.rb b/spec/support/rails_template.rb
index 3cba5d5..8ec2f4f 100644
--- a/spec/support/rails_template.rb
+++ b/spec/support/rails_template.rb
@@ -508,6 +508,12 @@ def filter_defaults_apply?
       filter :title_cont, as: :string,
                           extensions: { validate: ->(value) { value.match?(/\\d/) && "Title must not contain digits." } }
       filter :status, as: :select, collection: %w[draft published]
+
+      # Lands on the bare index, where the guard warns on the key Active Admin 4 also uses
+      # for :alert.
+      collection_action :poke do
+        redirect_to collection_path, alert: "poked"
+      end
     end
 
     ActiveAdmin.register Post, as: "EmptyDigitsPost" do

From 63e1d771a22b560119b971f6b98472c614079121 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 14:16:45 +0200
Subject: [PATCH 8/9] Tidy the Active Admin 4 support after review

Co-Authored-By: Clanker
---
 lib/active_admin_filter_extensions.rb              | 4 +++-
 lib/active_admin_filter_extensions/filters_form.rb | 4 ++--
 spec/integration/sidebar_spec.rb                   | 7 +++++++
 spec/support/rails_template.rb                     | 5 +++++
 tasks/test.rake                                    | 2 ++
 5 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/lib/active_admin_filter_extensions.rb b/lib/active_admin_filter_extensions.rb
index bb6638b..5fd4522 100644
--- a/lib/active_admin_filter_extensions.rb
+++ b/lib/active_admin_filter_extensions.rb
@@ -35,7 +35,9 @@ def notice_flash_key
 
     # Active Admin 4 moved the filters form helper and the Current Filters section.
     def aa_v4?
-      Gem::Version.new(ActiveAdmin::VERSION) >= Gem::Version.new("4.0.0.beta1")
+      return @aa_v4 if defined?(@aa_v4)
+
+      @aa_v4 = Gem::Version.new(ActiveAdmin::VERSION) >= Gem::Version.new("4.0.0.beta1")
     end
 
     # Active Admin 4's layout renders only the :error, :alert and :notice flash keys.
diff --git a/lib/active_admin_filter_extensions/filters_form.rb b/lib/active_admin_filter_extensions/filters_form.rb
index 231240c..656e9f3 100644
--- a/lib/active_admin_filter_extensions/filters_form.rb
+++ b/lib/active_admin_filter_extensions/filters_form.rb
@@ -27,8 +27,8 @@ module ResourceExtensionV4
     def filters_sidebar_section
       name = :filters
       ActiveAdmin::SidebarSection.new name, only: :index, if: -> { active_admin_config.filters.any? } do
-        h3 I18n.t("active_admin.sidebars.#{name}", default: name.to_s.titlecase),
-           class: "filters-form-title", "data-filter-extensions-title" => ""
+        title = I18n.t("active_admin.sidebars.#{name}", default: name.to_s.titlecase)
+        h3 title, class: "filters-form-title", "data-filter-extensions-title" => ""
         active_admin_filters_form_for assigns[:search], visible_filters, FORM_OPTIONS
       end
     end
diff --git a/spec/integration/sidebar_spec.rb b/spec/integration/sidebar_spec.rb
index ada6a6d..3b5aff0 100644
--- a/spec/integration/sidebar_spec.rb
+++ b/spec/integration/sidebar_spec.rb
@@ -20,6 +20,13 @@
     expect(page).to have_css(current_filters, text: "keep")
   end
 
+  it "keeps the Current Filters panel off where the resource turned it off" do
+    visit "/admin/quiet_default_posts"
+
+    expect(page).to have_css("#filters_sidebar_section")
+    expect(page).to have_no_css(current_filters)
+  end
+
   it "hides the Current Filters panel when nothing is filtered" do
     visit "/admin/no_defaults_posts"
 
diff --git a/spec/support/rails_template.rb b/spec/support/rails_template.rb
index 8ec2f4f..9278037 100644
--- a/spec/support/rails_template.rb
+++ b/spec/support/rails_template.rb
@@ -75,6 +75,11 @@ def current_admin_user
       filter :title, extensions: { default: "keep" }
     end
 
+    ActiveAdmin.register Post, as: "QuietDefaultPost" do
+      config.current_filters = false
+      filter :title, extensions: { default: "keep" }
+    end
+
     ActiveAdmin.register Post, as: "ScalarPost" do
       filter :title_cont, as: :string, extensions: { default: "keep" }
     end
diff --git a/tasks/test.rake b/tasks/test.rake
index b5ed0b0..9fb8b69 100644
--- a/tasks/test.rake
+++ b/tasks/test.rake
@@ -16,6 +16,8 @@ task :setup do
     -m spec/support/rails_template.rb
   ].join(" ")
 
+  # Plain `rake setup` has not activated the bundle, and Gem.loaded_specs needs it.
+  require "bundler/setup"
   # One app per Active Admin major: its installer writes different assets and initializers.
   aa_major = Gem.loaded_specs["activeadmin"].version.segments.first
   app_dir = "spec/rails/rails-#{Rails::VERSION::STRING}-aa#{aa_major}"

From e4db531c7ae6ca8bbd91af55e9c4f306e8910f68 Mon Sep 17 00:00:00 2001
From: Denis Talakevich <senid231@gmail.com>
Date: Thu, 12 Nov 2026 16:34:02 +0200
Subject: [PATCH 9/9] Remove app names from the spec template comments

Co-Authored-By: Clanker
---
 spec/support/rails_template.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/spec/support/rails_template.rb b/spec/support/rails_template.rb
index 9278037..a5f191b 100644
--- a/spec/support/rails_template.rb
+++ b/spec/support/rails_template.rb
@@ -294,7 +294,7 @@ def filter_defaults_apply?
       default_filters_notice "Showing the default window"
 
       # The capped window: never unbounded (required:), never wider than the cap, never before
-      # the retention floor - the didww-rs/pbx/nessie range guards, as options.
+      # the retention floor - the range guards apps write by hand, as options.
       filter :published_date, as: :date_range,
                               extensions: { required: true,
                                         max_range: 90.days,
@@ -412,7 +412,7 @@ def filter_defaults_apply?
     end
 
     ActiveAdmin.register Post, as: "RejectPost" do
-      # :reject - the didww-api-3 add_integer_filter_check shape: flash and bounce back.
+      # :reject - the shape of a hand-written filter check: flash and bounce back.
       filter :title_cont, as: :string,
                           extensions: { on_invalid: :reject,
                                     validate: ->(value) { value.match?(/\\d/) && "Title must not contain digits." } }