Fix the schema load test

And added changelog

changelogs/unreleased/force-post-migration-dir-schema-load.yml

+---
+title: Ensure the schema is loaded with post_migrations included
+merge_request:
+author:
+type: changed

spec/tasks/gitlab/db_rake_spec.rb

@@ -63,31 +63,35 @@ describe 'gitlab:db namespace rake task' do
     end
 
     context 'SKIP_POST_DEPLOYMENT_MIGRATIONS environment variable set' do
-      let :migrations_paths do
-        root = Rails::Paths::Root.new(Rails.root)
-        root.add('db/migrate')
-      end
+      let(:rails_paths) { { 'db' => ['db'], 'db/migrate' => ['db/migrate'] } }
 
       before do
         allow(ENV).to receive(:[]).and_call_original
         allow(ENV).to receive(:[]).with('SKIP_POST_DEPLOYMENT_MIGRATIONS').and_return true
 
-        # Our environment has already been loaded, so we need to pretent like post_migrations were not
-        allow(Rails.application.config.paths).to receive(:[]).and_call_original
-        allow(Rails.application.config.paths).to receive(:[]).with('db/migrate').and_return(migrations_paths)
-        allow(ActiveRecord::Migrator).to receive(:migrations_paths).and_return(migrations_paths)
+        # Our environment has already been loaded, so we need to pretend like post_migrations were not
+        allow(Rails.application.config).to receive(:paths).and_return(rails_paths)
+        allow(ActiveRecord::Migrator).to receive(:migrations_paths).and_return(rails_paths['db/migrate'].dup)
       end
 
       it 'adds post deployment migrations before schema load if the schema is not already loaded' do
         allow(ActiveRecord::Base.connection).to receive(:tables).and_return([])
-        expect(Gitlab::Database).to receive(:add_post_migrate_path_to_rails)
+        expect(Gitlab::Database).to receive(:add_post_migrate_path_to_rails).and_call_original
         expect(Rake::Task['db:schema:load']).to receive(:invoke)
         expect(Rake::Task['db:seed_fu']).to receive(:invoke)
         expect(Rake::Task['db:migrate']).not_to receive(:invoke)
-        expect(Rails.application.config.paths).to receive(:[]).with('db/migrate')
         expect { run_rake_task('gitlab:db:configure') }.not_to raise_error
+        expect(rails_paths['db/migrate'].include?(File.join(Rails.root, 'db', 'post_migrate'))).to be(true)
+      end
 
-        expect(migrations_paths.include?(File.join(Rails.root, 'db', 'post_migrate'))).to be(true)
+      it 'ignores post deployment migrations  when schema has already been loaded' do
+        allow(ActiveRecord::Base.connection).to receive(:tables).and_return(%w[table1 table2])
+        expect(Rake::Task['db:migrate']).to receive(:invoke)
+        expect(Gitlab::Database).not_to receive(:add_post_migrate_path_to_rails)
+        expect(Rake::Task['db:schema:load']).not_to receive(:invoke)
+        expect(Rake::Task['db:seed_fu']).not_to receive(:invoke)
+        expect { run_rake_task('gitlab:db:configure') }.not_to raise_error
+        expect(rails_paths['db/migrate'].include?(File.join(Rails.root, 'db', 'post_migrate'))).to be(false)
       end
     end
   end