Rails 6.0 beta support

Changes:

1. Fixes to the multi-threaded collection renderer.
2. Removes dev dependency on `factory_bot_rails`, instead using plain
   `factory_bot` (as we don't need reloading support anyway).
3. Uses git versions of `roadie-rails` and `rspec-rails` for Rails 6
   beta for now.

Fixes #801
Refs #800

.travis.yml

@@ -1,22 +1,71 @@
 language: ruby
 dist: xenial
 sudo: false
-rvm:
-- 2.3.8
-
 addons:
   apt:
     packages:
     - chromium-browser
 
 before_install:
-  # Rails 4.x requires bundler version < 2.0.
-  - >
-    if [[ $BUNDLE_GEMFILE == "${PWD}/spec/gemfiles/rails_4_2.gemfile" ]]; then
-      "find /home/travis/.rvm/rubies -wholename '*default/bundler-*.gemspec' -delete"
-      gem install bundler --version='~> 1.17'
-      bundler --version
-    fi
+  - script/travis-downgrade-bundler-on-old-rails.sh
+
+matrix:
+  include:
+    - gemfile: spec/gemfiles/rails_4_2.gemfile
+      rvm: 2.3.8
+      env: DB=sqlite3
+    - gemfile: spec/gemfiles/rails_4_2.gemfile
+      rvm: 2.3.8
+      env: DB=mysql2 DB_USERNAME=root DB_PASSWORD=""
+      services: mysql
+    - gemfile: spec/gemfiles/rails_4_2.gemfile
+      rvm: 2.3.8
+      env: DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
+      services: postgresql
+    - gemfile: spec/gemfiles/rails_5_0.gemfile
+      rvm: 2.3.8
+      env: DB=sqlite3
+    - gemfile: spec/gemfiles/rails_5_0.gemfile
+      rvm: 2.3.8
+      env: DB=mysql2 DB_USERNAME=root DB_PASSWORD=""
+      services: mysql
+    - gemfile: spec/gemfiles/rails_5_0.gemfile
+      rvm: 2.3.8
+      env: DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
+      services: postgresql
+    - gemfile: spec/gemfiles/rails_5_1.gemfile
+      rvm: 2.3.8
+      env: DB=sqlite3
+    - gemfile: spec/gemfiles/rails_5_1.gemfile
+      rvm: 2.3.8
+      env: DB=mysql2 DB_USERNAME=root DB_PASSWORD=""
+      services: mysql
+    - gemfile: spec/gemfiles/rails_5_1.gemfile
+      rvm: 2.3.8
+      env: DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
+      services: postgresql
+    - gemfile: spec/gemfiles/rails_5_2.gemfile
+      rvm: 2.3.8
+      env: DB=sqlite3
+    - gemfile: spec/gemfiles/rails_5_2.gemfile
+      rvm: 2.3.8
+      env: DB=mysql2 DB_USERNAME=root DB_PASSWORD=""
+      services: mysql
+    - gemfile: spec/gemfiles/rails_5_2.gemfile
+      rvm: 2.3.8
+      env: DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
+      services: postgresql
+    - gemfile: spec/gemfiles/rails_6_0.gemfile
+      rvm: 2.5.5
+      env: DB=sqlite3
+    - gemfile: spec/gemfiles/rails_6_0.gemfile
+      rvm: 2.5.5
+      env: DB=mysql2 DB_USERNAME=root DB_PASSWORD=""
+      services: mysql
+    - gemfile: spec/gemfiles/rails_6_0.gemfile
+      rvm: 2.5.5
+      env: DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
+      services: postgresql
 
 cache:
   bundler: true
@@ -28,23 +77,10 @@ cache:
   - spec/dummy/tmp/cache/onebox-views
 
 bundler_args: --path ../../vendor/bundle --without debug
-gemfile:
-  - spec/gemfiles/rails_4_2.gemfile
-  - spec/gemfiles/rails_5_0.gemfile
-  - spec/gemfiles/rails_5_1.gemfile
-  - spec/gemfiles/rails_5_2.gemfile
 env:
-  matrix:
-  # Username and password from http://docs.travis-ci.com/user/database-setup/
-  - DB=sqlite3
-  - DB=mysql2     DB_USERNAME=root     DB_PASSWORD=""
-  - DB=postgresql DB_USERNAME=postgres DB_PASSWORD=""
   global:
   - COVERAGE=1
   - TRAVIS=1
-services:
-- postgresql
-- mysql
 
 before_script:
 - curl -L https://codeclimate.com/downloads/test-reporter/test-reporter-latest-linux-amd64 > ./cc-test-reporter

Gemfile

@@ -2,14 +2,21 @@
 
 source 'https://rubygems.org'
 
-# Rails 5
-gem 'rails', '~> 5.2.2'
+gem 'rails', '~> 6.0.0.beta3'
+gem 'rails-i18n', '~> 6.0.0.beta1'
 
-# https://github.com/rails/rails/blob/v5.2.2/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb#L12
-gem 'sqlite3', '~> 1.3.6'
+# https://github.com/rails/rails/blob/v6.0.0.beta3/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb#L12
+gem 'sqlite3', '~> 1.3', '>= 1.3.6'
 
 group :test do
   gem 'rails-controller-testing'
+
+  # https://github.com/rspec/rspec-rails/issues/2103
+  gem 'rspec-rails', git: 'https://github.com/rspec/rspec-rails', branch: '4-0-dev'
+  gem 'rspec-core', git: 'https://github.com/rspec/rspec-core'
+  gem 'rspec-mocks', git: 'https://github.com/rspec/rspec-mocks'
+  gem 'rspec-support', git: 'https://github.com/rspec/rspec-support'
+  gem 'rspec-expectations', git: 'https://github.com/rspec/rspec-expectations'
 end
 
 gemspec

app/models/concerns/thredded/post_common.rb

@@ -23,7 +23,7 @@ module PostCommon
         result = all
         ActiveRecord::Associations::Preloader.new.preload(
           result.map(&:postable), :first_post,
-          Thredded::Post.where(<<~SQL.delete("\n"))
+          unscoped.where(<<~SQL.delete("\n"))
           #{posts_table_name}.created_at = (
           SELECT MAX(p2.created_at) from #{posts_table_name} p2 WHERE p2.postable_id = #{posts_table_name}.postable_id)
         SQL

db/upgrade_migrations/20170125033319_upgrade_v0_9_to_v0_10.rb

@@ -4,10 +4,16 @@
 
 class UpgradeV09ToV010 < Thredded::BaseMigration
   def up
-    remove_foreign_key :thredded_messageboard_users, :thredded_messageboards
+    if respond_to?(:foreign_key_exists?)
+      if foreign_key_exists?(:thredded_messageboard_users, :thredded_messageboards)
+        remove_foreign_key :thredded_messageboard_users, :thredded_messageboards
+      end
+      if foreign_key_exists?(:thredded_messageboard_users, :thredded_user_details)
+        remove_foreign_key :thredded_messageboard_users, :thredded_user_details
+      end
+    end
     add_foreign_key :thredded_messageboard_users, :thredded_messageboards,
                     column: :thredded_messageboard_id, on_delete: :cascade
-    remove_foreign_key :thredded_messageboard_users, :thredded_user_details
     add_foreign_key :thredded_messageboard_users, :thredded_user_details,
                     column: :thredded_user_detail_id, on_delete: :cascade
 

heroku.gemfile

@@ -1,13 +1,13 @@
 # frozen_string_literal: true
 
 source 'https://rubygems.org'
-ruby '2.5.3'
+ruby '2.5.5'
 
 gem 'thredded', path: File.dirname(__FILE__)
 
 gem 'mustache'
 
-gem 'rails', '~> 5.2.0'
+gem 'rails', '~> 6.0.0.beta3'
 
 # Use Uglifier as compressor for JavaScript assets
 gem 'uglifier'
@@ -16,12 +16,15 @@ gem 'uglifier'
 gem 'puma'
 gem 'pg'
 gem 'rails_email_preview', '>= 2.2.1'
-gem 'roadie-rails'
+
+# https://github.com/Mange/roadie-rails/pull/88
+gem 'roadie-rails', git: 'https://github.com/glebm/roadie-rails', branch: 'patch-2'
+
 gem 'turbolinks'
-gem 'rails-i18n'
+gem 'rails-i18n', '~> 6.0.0.beta1'
 gem 'kaminari-i18n'
 gem 'http_accept_language'
-gem 'factory_bot_rails'
+gem 'factory_bot'
 gem 'faker', '>= 1.6.2'
 gem 'twemoji'