Test against rails master

Appraisals

@@ -83,3 +83,20 @@ appraise 'activerecord_6.0.0' do
     gem 'sqlite3', '~> 1.4.0'
   end
 end
+
+appraise 'activerecord_master' do
+  gem 'actionpack', github: 'rails/rails', require: 'action_pack'
+  gem 'activerecord', github: 'rails/rails', require: 'active_record'
+  gem 'activesupport', github: 'rails/rails', require: 'active_support/all'
+
+  platforms :jruby do
+    gem 'activerecord-jdbcsqlite3-adapter'
+    gem 'jdbc-sqlite3'
+    gem 'jdbc-postgres'
+  end
+
+  platforms :ruby, :mswin, :mingw do
+    gem 'pg', '~> 1.1.4'
+    gem 'sqlite3', '~> 1.4.0'
+  end
+end

gemfiles/activerecord_master.gemfile

@@ -0,0 +1,20 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "actionpack", github: "rails/rails", require: "action_pack"
+gem "activerecord", github: "rails/rails", require: "active_record"
+gem "activesupport", github: "rails/rails", require: "active_support/all"
+
+platforms :jruby do
+  gem "activerecord-jdbcsqlite3-adapter"
+  gem "jdbc-sqlite3"
+  gem "jdbc-postgres"
+end
+
+platforms :ruby, :mswin, :mingw do
+  gem "pg", "~> 1.1.4"
+  gem "sqlite3", "~> 1.4.0"
+end
+
+gemspec path: "../"