From eea605f5fcd358a228b38422bcd0a7012590206b Mon Sep 17 00:00:00 2001
From: Igor Fedoronchuk <fedoronchuk@gmail.com>
Date: Thu, 1 Oct 2026 12:57:45 +0200
Subject: [PATCH] Key the dummy app on every input that builds it

Three ways the harness hid failures instead of reporting them.

The generated app was keyed on the Rails version alone, but
active_admin:install runs inside it, so Active Admin is an input too.
`AA=3.2.0 bundle exec rspec` silently reused the app built for 3.5 and
reported on a build it never produced -- including the invocation the
README documents. CI never saw it because runners start empty.

The reuse check was `unless File.exist?(RAILS_ROOT)`, but rails new creates
that directory before the template runs, so a template that failed halfway
left it behind and every later run skipped regeneration and died on
config/environment.rb instead of showing the real error. system's exit
status was discarded as well, in both the spec helper and the rake task.
Check for config/environment.rb, clear the directory first, and abort on
failure.

spec_helper also did `ENV['RAILS'] = Rails.version`, overwriting the
variable the Gemfile reads. CI sets 7.1.0, the Gemfile resolves 7.1.6, and
the rake setup child then evaluated `~> 7.1.6` against a lockfile recording
`~> 7.1.0` -- Bundler re-resolves and rewrites the lock as a side effect of
running tests. The only consumer was the path on the next line, which now
comes from TestAppPaths.

Naming follows active_admin_import, which already keys its apps this way.
---
 spec/spec_helper.rb            | 18 +++++++++++++-----
 spec/support/test_app_paths.rb | 19 +++++++++++++++++++
 tasks/test.rake                |  8 ++++++--
 3 files changed, 38 insertions(+), 7 deletions(-)
 create mode 100644 spec/support/test_app_paths.rb

diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index ae001dd..916bd09 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -12,11 +12,19 @@
 
 ENV['RAILS_ENV'] = 'test'
 require 'rails'
-ENV['RAILS'] = Rails.version
-ENV['RAILS_ROOT'] = File.expand_path("../rails/rails-#{ENV['RAILS']}", __FILE__)
-
-# Create the test app if it doesn't exist
-system 'rake setup' unless File.exist?(ENV['RAILS_ROOT'])
+require 'fileutils'
+require_relative 'support/test_app_paths'
+ENV['RAILS_ROOT'] = TestAppPaths.app_root
+
+# Create the test app if it doesn't exist. rails new creates the target
+# directory before the template runs, so a template that fails halfway leaves
+# the directory behind and every later run would skip regeneration and die on
+# config/environment.rb instead of reporting the real error. Check the file the
+# suite actually loads, and refuse to continue if the build did not succeed.
+unless File.exist?(File.join(ENV['RAILS_ROOT'], 'config', 'environment.rb'))
+  FileUtils.rm_rf(ENV['RAILS_ROOT'])
+  abort 'rake setup failed; dummy app not built' unless system('rake setup')
+end
 
 require 'active_model'
 # require ActiveRecord to ensure that Ransack loads correctly
diff --git a/spec/support/test_app_paths.rb b/spec/support/test_app_paths.rb
new file mode 100644
index 0000000..d77fe5d
--- /dev/null
+++ b/spec/support/test_app_paths.rb
@@ -0,0 +1,19 @@
+require 'rails/version'
+
+# Where the generated dummy app lives, and under what name.
+#
+# The name has to carry every input that changes what gets generated.
+# Keying on the Rails version alone meant `AA=3.2.0 rspec` silently reused an
+# app whose active_admin:install had been run by a different Active Admin, so
+# the leg reported on a build it never produced.
+module TestAppPaths
+  module_function
+
+  def app_dir_name
+    "rails-#{Rails::VERSION::STRING}-aa#{ENV['AA'] || 'default'}"
+  end
+
+  def app_root
+    File.expand_path("../rails/#{app_dir_name}", __dir__)
+  end
+end
diff --git a/tasks/test.rake b/tasks/test.rake
index e7d8dab..689b7fa 100644
--- a/tasks/test.rake
+++ b/tasks/test.rake
@@ -1,6 +1,7 @@
+require_relative '../spec/support/test_app_paths'
+
 desc 'Creates a test rails app for the specs to run against'
 task :setup do
-  require 'rails/version'
 
   rails_new_args = %w[
     --skip-turbolinks
@@ -10,5 +11,8 @@ task :setup do
     spec/support/rails_template.rb
   ].join(' ')
 
-  system "bundle exec rails new spec/rails/rails-#{Rails::VERSION::STRING} #{rails_new_args}"
+  puts "[setup] Rails #{Rails::VERSION::STRING} / Active Admin #{ENV['AA'] || '(Gemfile default)'}"
+
+  abort 'rails new failed' unless
+    system("bundle exec rails new spec/rails/#{TestAppPaths.app_dir_name} #{rails_new_args}")
 end