Add testing support for MySQL and PostgreSQL databases

ransack.gemspec

@@ -21,6 +21,8 @@ Gem::Specification.new do |s|
   s.add_development_dependency 'machinist', '~> 1.0.6'
   s.add_development_dependency 'faker', '~> 0.9.5'
   s.add_development_dependency 'sqlite3', '~> 1.3.3'
+  s.add_development_dependency 'pg', '0.17.0'
+  s.add_development_dependency 'mysql2', '0.3.13'
 
   s.files         = `git ls-files`.split("\n")
   s.test_files    = `git ls-files -- {test,spec,features}/*`.split("\n")

spec/spec_helper.rb

@@ -24,7 +24,8 @@ RSpec.configure do |config|
 
   config.before(:suite) do
     puts '=' * 80
-    puts "Running specs against ActiveRecord #{ActiveRecord::VERSION::STRING} and ARel #{Arel::VERSION}..."
+    connection_name = ActiveRecord::Base.connection.adapter_name
+    puts "Running specs against #{connection_name}, ActiveRecord #{ActiveRecord::VERSION::STRING} and ARel #{Arel::VERSION}..."
     puts '=' * 80
     Schema.create
   end

spec/support/schema.rb

@@ -1,9 +1,28 @@
 require 'active_record'
 
-ActiveRecord::Base.establish_connection(
-  adapter: 'sqlite3',
-  database: ':memory:'
-)
+case ENV['DB']
+when "mysql"
+  ActiveRecord::Base.establish_connection(
+    adapter:  'mysql2',
+    database: 'ransack',
+    encoding: 'utf8'
+  )
+when "postgres"
+  ActiveRecord::Base.establish_connection(
+    adapter: 'postgresql',
+    database: 'ransack',
+    username: 'postgres',
+    min_messages: 'warning'
+  )
+else
+  # Assume SQLite3
+  ActiveRecord::Base.establish_connection(
+    adapter: 'sqlite3',
+    database: ':memory:'
+  )
+end
+
+
 
 class Person < ActiveRecord::Base
   default_scope { order(id: :desc) }