Updated dependency on "minitest" and fixed code incompatible code

Note: Still does not run on Ruby 2.2:

      elasticsearch-model/test/test_helper.rb:32:in `<top (required)>': cannot load such file -- test/unit (LoadError)

Author: karmi

elasticsearch-model/elasticsearch-model.gemspec

@@ -41,7 +41,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "will_paginate"
   # NOTE: Do not add Mongoid here, keep only in 3/4 files
 
-  s.add_development_dependency "minitest", "~> 4.0"
+  s.add_development_dependency "minitest", "~> 4"
   s.add_development_dependency "shoulda-context"
   s.add_development_dependency "mocha"
   s.add_development_dependency "turn"

elasticsearch-model/test/test_helper.rb

@@ -10,7 +10,8 @@
 
 puts '-'*80
 
-require 'test/unit'
+require 'minitest/autorun'
+begin; require 'test/unit'; rescue LoadError; end
 require 'shoulda-context'
 require 'mocha/setup'
 require 'turn' unless ENV["TM_FILEPATH"] || ENV["NOTURN"] || RUBY_1_8
@@ -28,6 +29,12 @@
 require 'elasticsearch/extensions/test/cluster'
 require 'elasticsearch/extensions/test/startup_shutdown'
 
+module Test
+  module Unit
+    class TestCase < MiniTest::Unit::TestCase; end
+  end
+end unless defined?(::Test::Unit::TestCase)
+
 module Elasticsearch
   module Test
     class IntegrationTestCase < ::Test::Unit::TestCase

elasticsearch-persistence/elasticsearch-persistence.gemspec

@@ -39,7 +39,7 @@ Gem::Specification.new do |s|
 
   s.add_development_dependency "elasticsearch-extensions"
 
-  s.add_development_dependency "minitest", "~> 4.0"
+  s.add_development_dependency "minitest", "~> 4"
   s.add_development_dependency "shoulda-context"
   s.add_development_dependency "mocha"
   s.add_development_dependency "turn"

elasticsearch-rails/elasticsearch-rails.gemspec

@@ -34,7 +34,7 @@ Gem::Specification.new do |s|
 
   s.add_development_dependency "lograge"
 
-  s.add_development_dependency "minitest", "~> 4.0"
+  s.add_development_dependency "minitest", "~> 4"
   s.add_development_dependency "shoulda-context"
   s.add_development_dependency "mocha"
   s.add_development_dependency "turn"