Improve setup steps for new contributors

I felt some pain while trying to get the tests running. These changes are intended to ease that pain for others in the future.

Author: jnraine

README.md

@@ -1,6 +1,7 @@
 # PolymorphicIntegerType
 
 Rails' polymorphic associations are pretty useful. The example they give to set it up looks like:
+
 ```ruby
 class Picture < ActiveRecord::Base
   belongs_to :imageable, polymorphic: true
@@ -16,6 +17,7 @@ end
 ```
 
 With a migration that looks like:
+
 ```ruby
 class CreatePictures < ActiveRecord::Migration
   def change
@@ -52,6 +54,7 @@ For Rails 3.2 use version < 2. Version >= 2 has been tested on Rails 4.2 and Rub
 The gem is pretty straightforward to use.
 
 First, include the extensions module and add the `integer_type`  option to the associations that are going to be using this. (That way it will play nicely with polymorphic associations whose type you would rather leave as a string.)
+
 ```ruby
 class Picture < ActiveRecord::Base
   include PolymorphicIntegerType::Extensions
@@ -70,6 +73,7 @@ end
 ```
 
 Second, you need to create a mapping for the polymorphic associations. This should be loaded before the models. Putting it in an initializer is good (`config/initializers/polymorphic_type_mapping.rb`)
+
 ```ruby
 PolymorphicIntegerType::Mapping.configuration do |config|
 
@@ -81,6 +85,7 @@ end
 Note: The mapping here can start from whatever integer you wish, but I would advise not using 0. The reason being that if you had a new class, for instance `Avatar`, and also wanted to use this polymorphic association but forgot to include it in the mapping, it would effectively get `to_i` called on it and stored in the database. `"Avatar".to_i == 0`, so if your mapping included 0, this would create a weird bug. 
 
 If you want to convert a polymorphic association that is already a string, you'll need to set up a migration. (Assuming SQL for the time being, but this should be pretty straightforward.)
+
 ```ruby
 class PictureToPolymorphicIntegerType < ActiveRecord::Migration
 
@@ -125,8 +130,18 @@ end
 ```
 
 Lastly, you will need to be careful of any place where you are doing raw SQL queries with the string (`imageable_type = 'Employee'`). They should use the integer instead.
-  
 
+## Setup
+
+You'll need to have git, Ruby, and MySQL. Then get up and running with a few commands:
+
+```bash
+$ git clone ...
+$ bundle install
+$ vim spec/support/database.yml # Update username and password
+$ bin/setup
+$ bundle exec rspec
+```
 
 ## Contributing
 

Rakefile

@@ -1 +1,39 @@
 require "bundler/gem_tasks"
+require "yaml"
+require "active_record"
+
+namespace :db do
+  database_config = YAML.load(File.open("./spec/support/database.yml"))
+  admin_database_config = database_config.merge(database: "mysql")
+  migration_path = File.expand_path("./spec/support/migrations")
+
+  desc "Create the database"
+  task :create do
+    ActiveRecord::Base.establish_connection(admin_database_config)
+    ActiveRecord::Base.connection.create_database(database_config.fetch(:database))
+    puts "Database created."
+  end
+
+  desc "Migrate the database"
+  task :migrate do
+    ActiveRecord::Base.establish_connection(database_config)
+    ActiveRecord::Migrator.migrate(migration_path)
+    Rake::Task["db:schema"].invoke
+    puts "Database migrated."
+  end
+
+  desc "Drop the database"
+  task :drop do
+    ActiveRecord::Base.establish_connection(admin_database_config)
+    ActiveRecord::Base.connection.drop_database(database_config.fetch(:database))
+    puts "Database deleted."
+  end
+
+  desc "Reset the database"
+  task reset: [:drop, :create, :migrate]
+    desc 'Create a db/schema.rb file that is portable against any DB supported by AR'
+
+  task :schema do
+    # Noop to make ActiveRecord happy
+  end
+end

bin/setup

@@ -0,0 +1,2 @@
+#!/bin/bash
+bundle exec rake db:drop db:create db:migrate

polymorphic_integer_type.gemspec

@@ -24,5 +24,4 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "activerecord", "4.2.0"
   spec.add_development_dependency "mysql2", "0.3.16"
   spec.add_development_dependency "byebug"
-
 end

spec/spec_helper.rb

@@ -1,4 +1,5 @@
-require 'support/active_record'
+require 'yaml'
+require 'active_record'
 require 'polymorphic_integer_type'
 require 'support/configuration'
 require 'support/link'
@@ -8,26 +9,16 @@
 require 'support/food'
 require 'support/drink'
 
-
-
 RSpec.configure do |config|
-
   config.before(:suite) do
-    ActiveRecord::Migrator.up "#{File.dirname(__FILE__)}/support/migrations"
+    database_config = YAML.load(File.open("#{File.dirname(__FILE__)}/support/database.yml"))
+    ActiveRecord::Base.establish_connection(database_config)
   end
 
-  # No need to return the run the down migration after the test
-  # but useful while in development
-  # config.after(:suite) do
-  #   ActiveRecord::Migrator.down "#{File.dirname(__FILE__)}/support/migrations"
-  # end
-
-
   config.around do |example|
     ActiveRecord::Base.transaction do
       example.run
       raise ActiveRecord::Rollback
     end
   end
-
 end

spec/support/active_record.rb

@@ -0,0 +1,6 @@
+---
+:adapter: mysql2
+:host: localhost
+:database: polymorphic_integer_type_test
+:username: root
+:password: ''