rails/railties/test/application/test_test.rb

require 'isolation/abstract_unit'

module ApplicationTests
  class TestTest < ActiveSupport::TestCase
    include ActiveSupport::Testing::Isolation

    def setup
      build_app
      boot_rails
    end

    def teardown
      teardown_app
    end

    test "truth" do
      app_file 'test/unit/foo_test.rb', <<-RUBY
        require 'test_helper'

        class FooTest < ActiveSupport::TestCase
          def test_truth
            assert true
          end
        end
      RUBY

      assert_successful_test_run 'unit/foo_test.rb'
    end

    test "integration test" do
      controller 'posts', <<-RUBY
        class PostsController < ActionController::Base
        end
      RUBY

      app_file 'app/views/posts/index.html.erb', <<-HTML
        Posts#index
      HTML

      app_file 'test/integration/posts_test.rb', <<-RUBY
        require 'test_helper'

        class PostsTest < ActionDispatch::IntegrationTest
          def test_index
            get '/posts'
            assert_response :success
            assert_includes @response.body, 'Posts#index'
          end
        end
      RUBY

      assert_successful_test_run 'integration/posts_test.rb'
    end

    test "enable full backtraces on test failures" do
      app_file 'test/unit/failing_test.rb', <<-RUBY
        require 'test_helper'

        class FailingTest < ActiveSupport::TestCase
          def test_failure
            raise "fail"
          end
        end
      RUBY

      output = run_test_file('unit/failing_test.rb', env: { "BACKTRACE" => "1" })
      assert_match %r{test/unit/failing_test\.rb}, output
      assert_match %r{test/unit/failing_test\.rb:4}, output
    end

    test "ruby schema migrations" do
      output  = script('generate model user name:string')
      version = output.match(/(\d+)_create_users\.rb/)[1]

      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'

        class UserTest < ActiveSupport::TestCase
          test "user" do
            User.create! name: "Jon"
          end
        end
      RUBY
      app_file 'db/schema.rb', ''

      assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"

      app_file 'db/schema.rb', <<-RUBY
        ActiveRecord::Schema.define(version: #{version}) do
          create_table :users do |t|
            t.string :name
          end
        end
      RUBY

      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
        Rails.application.config.active_record.maintain_test_schema = false
      RUBY

      assert_unsuccessful_run "models/user_test.rb", "Could not find table 'users'"

      File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"

      result = assert_successful_test_run('models/user_test.rb')
      assert !result.include?("create_table(:users)")
    end

    test "sql structure migrations" do
      output  = script('generate model user name:string')
      version = output.match(/(\d+)_create_users\.rb/)[1]

      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'

        class UserTest < ActiveSupport::TestCase
          test "user" do
            User.create! name: "Jon"
          end
        end
      RUBY

      app_file 'db/structure.sql', ''
      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
        Rails.application.config.active_record.schema_format = :sql
      RUBY

      assert_unsuccessful_run "models/user_test.rb", "Migrations are pending"

      app_file 'db/structure.sql', <<-SQL
        CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
        CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
        CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
        INSERT INTO schema_migrations (version) VALUES ('#{version}');
      SQL

      app_file 'config/initializers/disable_maintain_test_schema.rb', <<-RUBY
        Rails.application.config.active_record.maintain_test_schema = false
      RUBY

      assert_unsuccessful_run "models/user_test.rb", "Could not find table 'users'"

      File.delete "#{app_path}/config/initializers/disable_maintain_test_schema.rb"

      assert_successful_test_run('models/user_test.rb')
    end

    test "sql structure migrations when adding column to existing table" do
      output_1  = script('generate model user name:string')
      version_1 = output_1.match(/(\d+)_create_users\.rb/)[1]

      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'
        class UserTest < ActiveSupport::TestCase
          test "user" do
            User.create! name: "Jon"
          end
        end
      RUBY

      app_file 'config/initializers/enable_sql_schema_format.rb', <<-RUBY
        Rails.application.config.active_record.schema_format = :sql
      RUBY

      app_file 'db/structure.sql', <<-SQL
        CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
        CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
        CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255));
        INSERT INTO schema_migrations (version) VALUES ('#{version_1}');
      SQL

      assert_successful_test_run('models/user_test.rb')

      output_2  = script('generate migration add_email_to_users')
      version_2 = output_2.match(/(\d+)_add_email_to_users\.rb/)[1]

      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'

        class UserTest < ActiveSupport::TestCase
          test "user" do
            User.create! name: "Jon", email: "jon@doe.com"
          end
        end
      RUBY

      app_file 'db/structure.sql', <<-SQL
        CREATE TABLE "schema_migrations" ("version" varchar(255) NOT NULL);
        CREATE UNIQUE INDEX "unique_schema_migrations" ON "schema_migrations" ("version");
        CREATE TABLE "users" ("id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, "name" varchar(255), "email" varchar(255));
        INSERT INTO schema_migrations (version) VALUES ('#{version_1}');
        INSERT INTO schema_migrations (version) VALUES ('#{version_2}');
      SQL

      assert_successful_test_run('models/user_test.rb')
    end

    # TODO: would be nice if we could detect the schema change automatically.
    # For now, the user has to synchronize the schema manually.
    # This test-case serves as a reminder for this use-case.
    test "manually synchronize test schema after rollback" do
      output  = script('generate model user name:string')
      version = output.match(/(\d+)_create_users\.rb/)[1]

      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'

        class UserTest < ActiveSupport::TestCase
          test "user" do
            assert_equal ["id", "name"], User.columns_hash.keys
          end
        end
      RUBY
      app_file 'db/schema.rb', <<-RUBY
        ActiveRecord::Schema.define(version: #{version}) do
          create_table :users do |t|
            t.string :name
          end
        end
      RUBY

      assert_successful_test_run "models/user_test.rb"

      # Simulate `db:rollback` + edit of the migration file + `db:migrate`
      app_file 'db/schema.rb', <<-RUBY
        ActiveRecord::Schema.define(version: #{version}) do
          create_table :users do |t|
            t.string :name
            t.integer :age
          end
        end
      RUBY

      assert_successful_test_run "models/user_test.rb"

      Dir.chdir(app_path) { `bin/rake db:test:prepare` }

      assert_unsuccessful_run "models/user_test.rb", <<-ASSERTION
Expected: ["id", "name"]
  Actual: ["id", "name", "age"]
      ASSERTION
    end

    test "hooks for plugins" do
      output  = script('generate model user name:string')
      version = output.match(/(\d+)_create_users\.rb/)[1]

      app_file 'lib/tasks/hooks.rake', <<-RUBY
        task :before_hook do
          has_user_table = ActiveRecord::Base.connection.table_exists?('users')
          puts "before: " + has_user_table.to_s
        end

        task :after_hook do
          has_user_table = ActiveRecord::Base.connection.table_exists?('users')
          puts "after: " + has_user_table.to_s
        end

        Rake::Task["db:test:prepare"].enhance [:before_hook] do
          Rake::Task[:after_hook].invoke
        end
      RUBY
      app_file 'test/models/user_test.rb', <<-RUBY
        require 'test_helper'
        class UserTest < ActiveSupport::TestCase
          test "user" do
            User.create! name: "Jon"
          end
        end
      RUBY

      # Simulate `db:migrate`
      app_file 'db/schema.rb', <<-RUBY
        ActiveRecord::Schema.define(version: #{version}) do
          create_table :users do |t|
            t.string :name
          end
        end
      RUBY

      output = assert_successful_test_run "models/user_test.rb"
      assert_includes output, "before: false\nafter: true"

      # running tests again won't trigger a schema update
      output = assert_successful_test_run "models/user_test.rb"
      assert_not_includes output, "before:"
      assert_not_includes output, "after:"
    end

    private
      def assert_unsuccessful_run(name, message)
        result = run_test_file(name)
        assert_not_equal 0, $?.to_i
        assert result.include?(message)
        result
      end

      def assert_successful_test_run(name)
        result = run_test_file(name)
        assert_equal 0, $?.to_i, result
        result
      end

      def run_test_file(name, options = {})
        Dir.chdir(app_path) { `bin/rails test "#{app_path}/test/#{name}" 2>&1` }
      end
  end
end