Completely remove potential global state leaks in ActiveModel tests.

ActiveModel tests can now be run in random order.

7 files changed, 136 insertions, 110 deletions

diff --git a/activemodel/test/cases/attribute_methods_test.rb b/activemodel/test/cases/attribute_methods_test.rb
index e9cb5ccc96..e81b7ac424 100644
--- a/activemodel/test/cases/attribute_methods_test.rb
+++ b/activemodel/test/cases/attribute_methods_test.rb
@@ -104,10 +104,14 @@ class AttributeMethodsTest < ActiveModel::TestCase
   end
 
   test '#define_attribute_method generates attribute method' do
-    ModelWithAttributes.define_attribute_method(:foo)
+    begin
+      ModelWithAttributes.define_attribute_method(:foo)
 
-    assert_respond_to ModelWithAttributes.new, :foo
-    assert_equal "value of foo", ModelWithAttributes.new.foo
+      assert_respond_to ModelWithAttributes.new, :foo
+      assert_equal "value of foo", ModelWithAttributes.new.foo
+    ensure
+      ModelWithAttributes.undefine_attribute_methods
+    end
   end
 
   test '#define_attribute_method does not generate attribute method if already defined in attribute module' do
@@ -134,24 +138,36 @@ class AttributeMethodsTest < ActiveModel::TestCase
   end
 
   test '#define_attribute_method generates attribute method with invalid identifier characters' do
-    ModelWithWeirdNamesAttributes.define_attribute_method(:'a?b')
+    begin
+      ModelWithWeirdNamesAttributes.define_attribute_method(:'a?b')
 
-    assert_respond_to ModelWithWeirdNamesAttributes.new, :'a?b'
-    assert_equal "value of a?b", ModelWithWeirdNamesAttributes.new.send('a?b')
+      assert_respond_to ModelWithWeirdNamesAttributes.new, :'a?b'
+      assert_equal "value of a?b", ModelWithWeirdNamesAttributes.new.send('a?b')
+    ensure
+      ModelWithWeirdNamesAttributes.undefine_attribute_methods
+    end
   end
 
   test '#define_attribute_methods works passing multiple arguments' do
-    ModelWithAttributes.define_attribute_methods(:foo, :baz)
+    begin
+      ModelWithAttributes.define_attribute_methods(:foo, :baz)
 
-    assert_equal "value of foo", ModelWithAttributes.new.foo
-    assert_equal "value of baz", ModelWithAttributes.new.baz
+      assert_equal "value of foo", ModelWithAttributes.new.foo
+      assert_equal "value of baz", ModelWithAttributes.new.baz
+    ensure
+      ModelWithAttributes.undefine_attribute_methods
+    end
   end
 
   test '#define_attribute_methods generates attribute methods' do
-    ModelWithAttributes.define_attribute_methods(:foo)
+    begin
+      ModelWithAttributes.define_attribute_methods(:foo)
 
-    assert_respond_to ModelWithAttributes.new, :foo
-    assert_equal "value of foo", ModelWithAttributes.new.foo
+      assert_respond_to ModelWithAttributes.new, :foo
+      assert_equal "value of foo", ModelWithAttributes.new.foo
+    ensure
+      ModelWithAttributes.undefine_attribute_methods
+    end
   end
 
   test '#alias_attribute generates attribute_aliases lookup hash' do
@@ -164,26 +180,38 @@ class AttributeMethodsTest < ActiveModel::TestCase
   end
 
   test '#define_attribute_methods generates attribute methods with spaces in their names' do
-    ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
+    begin
+      ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
 
-    assert_respond_to ModelWithAttributesWithSpaces.new, :'foo bar'
-    assert_equal "value of foo bar", ModelWithAttributesWithSpaces.new.send(:'foo bar')
+      assert_respond_to ModelWithAttributesWithSpaces.new, :'foo bar'
+      assert_equal "value of foo bar", ModelWithAttributesWithSpaces.new.send(:'foo bar')
+    ensure
+      ModelWithAttributesWithSpaces.undefine_attribute_methods
+    end
   end
 
   test '#alias_attribute works with attributes with spaces in their names' do
-    ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
-    ModelWithAttributesWithSpaces.alias_attribute(:'foo_bar', :'foo bar')
+    begin
+      ModelWithAttributesWithSpaces.define_attribute_methods(:'foo bar')
+      ModelWithAttributesWithSpaces.alias_attribute(:'foo_bar', :'foo bar')
 
-    assert_equal "value of foo bar", ModelWithAttributesWithSpaces.new.foo_bar
+      assert_equal "value of foo bar", ModelWithAttributesWithSpaces.new.foo_bar
+    ensure
+      ModelWithAttributesWithSpaces.undefine_attribute_methods
+    end
   end
 
   test '#alias_attribute works with attributes named as a ruby keyword' do
-    ModelWithRubyKeywordNamedAttributes.define_attribute_methods([:begin, :end])
-    ModelWithRubyKeywordNamedAttributes.alias_attribute(:from, :begin)
-    ModelWithRubyKeywordNamedAttributes.alias_attribute(:to, :end)
-
-    assert_equal "value of begin", ModelWithRubyKeywordNamedAttributes.new.from
-    assert_equal "value of end", ModelWithRubyKeywordNamedAttributes.new.to
+    begin
+      ModelWithRubyKeywordNamedAttributes.define_attribute_methods([:begin, :end])
+      ModelWithRubyKeywordNamedAttributes.alias_attribute(:from, :begin)
+      ModelWithRubyKeywordNamedAttributes.alias_attribute(:to, :end)
+
+      assert_equal "value of begin", ModelWithRubyKeywordNamedAttributes.new.from
+      assert_equal "value of end", ModelWithRubyKeywordNamedAttributes.new.to
+    ensure
+      ModelWithRubyKeywordNamedAttributes.undefine_attribute_methods
+    end
   end
 
   test '#undefine_attribute_methods removes attribute methods' do
diff --git a/activemodel/test/cases/secure_password_test.rb b/activemodel/test/cases/secure_password_test.rb
index ffc534f0f4..d603dee73e 100644
--- a/activemodel/test/cases/secure_password_test.rb
+++ b/activemodel/test/cases/secure_password_test.rb
@@ -4,6 +4,7 @@ require 'models/visitor'
 
 class SecurePasswordTest < ActiveModel::TestCase
   setup do
+    @original_min_cost = ActiveModel::SecurePassword.min_cost
     ActiveModel::SecurePassword.min_cost = true
 
     @user = User.new
@@ -15,7 +16,7 @@ class SecurePasswordTest < ActiveModel::TestCase
   end
 
   teardown do
-    ActiveModel::SecurePassword.min_cost = false
+    ActiveModel::SecurePassword.min_cost = @original_min_cost
   end
 
   test "create and updating without validations" do
@@ -157,42 +158,29 @@ class SecurePasswordTest < ActiveModel::TestCase
   end
 
   test "Password digest cost defaults to bcrypt default cost when min_cost is false" do
-    original_min_cost = ActiveModel::SecurePassword.min_cost
     ActiveModel::SecurePassword.min_cost = false
 
-    begin
-      @user.password = "secret"
-      assert_equal BCrypt::Engine::DEFAULT_COST, @user.password_digest.cost
-    ensure
-      ActiveModel::SecurePassword.min_cost = original_min_cost
-    end
+    @user.password = "secret"
+    assert_equal BCrypt::Engine::DEFAULT_COST, @user.password_digest.cost
   end
 
   test "Password digest cost honors bcrypt cost attribute when min_cost is false" do
-    original_min_cost = ActiveModel::SecurePassword.min_cost
-    original_cost = BCrypt::Engine.cost
-
-    ActiveModel::SecurePassword.min_cost = false
-    BCrypt::Engine.cost = 5
-
     begin
+      original_bcrypt_cost = BCrypt::Engine.cost
+      ActiveModel::SecurePassword.min_cost = false
+      BCrypt::Engine.cost = 5
+
       @user.password = "secret"
       assert_equal BCrypt::Engine.cost, @user.password_digest.cost
     ensure
-      ActiveModel::SecurePassword.min_cost = original_min_cost
-      BCrypt::Engine.cost = original_cost
+      BCrypt::Engine.cost = original_bcrypt_cost
     end
   end
 
   test "Password digest cost can be set to bcrypt min cost to speed up tests" do
-    original_min_cost = ActiveModel::SecurePassword.min_cost
     ActiveModel::SecurePassword.min_cost = true
 
-    begin
-      @user.password = "secret"
-      assert_equal BCrypt::Engine::MIN_COST, @user.password_digest.cost
-    ensure
-      ActiveModel::SecurePassword.min_cost = original_min_cost
-    end
+    @user.password = "secret"
+    assert_equal BCrypt::Engine::MIN_COST, @user.password_digest.cost
   end
 end
diff --git a/activemodel/test/cases/serializers/json_serialization_test.rb b/activemodel/test/cases/serializers/json_serialization_test.rb
index bc185c737f..60414a6570 100644
--- a/activemodel/test/cases/serializers/json_serialization_test.rb
+++ b/activemodel/test/cases/serializers/json_serialization_test.rb
@@ -30,11 +30,6 @@ class JsonSerializationTest < ActiveModel::TestCase
     @contact.preferences = { 'shows' => 'anime' }
   end
 
-  def teardown
-    # set to the default value
-    Contact.include_root_in_json = false
-  end
-
   test "should not include root in json (class method)" do
     json = @contact.to_json
 
@@ -47,19 +42,25 @@ class JsonSerializationTest < ActiveModel::TestCase
   end
 
   test "should include root in json if include_root_in_json is true" do
-    Contact.include_root_in_json = true
-    json = @contact.to_json
-
-    assert_match %r{^\{"contact":\{}, json
-    assert_match %r{"name":"Konata Izumi"}, json
-    assert_match %r{"age":16}, json
-    assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
-    assert_match %r{"awesome":true}, json
-    assert_match %r{"preferences":\{"shows":"anime"\}}, json
+    begin
+      original_include_root_in_json = Contact.include_root_in_json
+      Contact.include_root_in_json = true
+      json = @contact.to_json
+
+      assert_match %r{^\{"contact":\{}, json
+      assert_match %r{"name":"Konata Izumi"}, json
+      assert_match %r{"age":16}, json
+      assert json.include?(%("created_at":#{ActiveSupport::JSON.encode(Time.utc(2006, 8, 1))}))
+      assert_match %r{"awesome":true}, json
+      assert_match %r{"preferences":\{"shows":"anime"\}}, json
+    ensure
+      Contact.include_root_in_json = original_include_root_in_json
+    end
   end
 
   test "should include root in json (option) even if the default is set to false" do
     json = @contact.to_json(root: true)
+
     assert_match %r{^\{"contact":\{}, json
   end
 
@@ -145,13 +146,18 @@ class JsonSerializationTest < ActiveModel::TestCase
   end
 
   test "as_json should return a hash if include_root_in_json is true" do
-    Contact.include_root_in_json = true
-    json = @contact.as_json
-
-    assert_kind_of Hash, json
-    assert_kind_of Hash, json['contact']
-    %w(name age created_at awesome preferences).each do |field|
-      assert_equal @contact.send(field), json['contact'][field]
+    begin
+      original_include_root_in_json = Contact.include_root_in_json
+      Contact.include_root_in_json = true
+      json = @contact.as_json
+
+      assert_kind_of Hash, json
+      assert_kind_of Hash, json['contact']
+      %w(name age created_at awesome preferences).each do |field|
+        assert_equal @contact.send(field), json['contact'][field]
+      end
+    ensure
+      Contact.include_root_in_json = original_include_root_in_json
     end
   end
 
diff --git a/activemodel/test/cases/serializers/xml_serialization_test.rb b/activemodel/test/cases/serializers/xml_serialization_test.rb
index 11ee17bb27..73f316d5e0 100644
--- a/activemodel/test/cases/serializers/xml_serialization_test.rb
+++ b/activemodel/test/cases/serializers/xml_serialization_test.rb
@@ -57,48 +57,48 @@ class XmlSerializationTest < ActiveModel::TestCase
   end
 
   test "should serialize default root" do
-    @xml = @contact.to_xml
-    assert_match %r{^<contact>},  @xml
-    assert_match %r{</contact>$}, @xml
+    xml = @contact.to_xml
+    assert_match %r{^<contact>},  xml
+    assert_match %r{</contact>$}, xml
   end
 
   test "should serialize namespaced root" do
-    @xml = Admin::Contact.new(@contact.attributes).to_xml
-    assert_match %r{^<contact>},  @xml
-    assert_match %r{</contact>$}, @xml
+    xml = Admin::Contact.new(@contact.attributes).to_xml
+    assert_match %r{^<contact>},  xml
+    assert_match %r{</contact>$}, xml
   end
 
   test "should serialize default root with namespace" do
-    @xml = @contact.to_xml namespace: "http://xml.rubyonrails.org/contact"
-    assert_match %r{^<contact xmlns="http://xml.rubyonrails.org/contact">}, @xml
-    assert_match %r{</contact>$}, @xml
+    xml = @contact.to_xml namespace: "http://xml.rubyonrails.org/contact"
+    assert_match %r{^<contact xmlns="http://xml.rubyonrails.org/contact">}, xml
+    assert_match %r{</contact>$}, xml
   end
 
   test "should serialize custom root" do
-    @xml = @contact.to_xml root: 'xml_contact'
-    assert_match %r{^<xml-contact>},  @xml
-    assert_match %r{</xml-contact>$}, @xml
+    xml = @contact.to_xml root: 'xml_contact'
+    assert_match %r{^<xml-contact>},  xml
+    assert_match %r{</xml-contact>$}, xml
   end
 
   test "should allow undasherized tags" do
-    @xml = @contact.to_xml root: 'xml_contact', dasherize: false
-    assert_match %r{^<xml_contact>},  @xml
-    assert_match %r{</xml_contact>$}, @xml
-    assert_match %r{<created_at},     @xml
+    xml = @contact.to_xml root: 'xml_contact', dasherize: false
+    assert_match %r{^<xml_contact>},  xml
+    assert_match %r{</xml_contact>$}, xml
+    assert_match %r{<created_at},     xml
   end
 
   test "should allow camelized tags" do
-    @xml = @contact.to_xml root: 'xml_contact', camelize: true
-    assert_match %r{^<XmlContact>},  @xml
-    assert_match %r{</XmlContact>$}, @xml
-    assert_match %r{<CreatedAt},     @xml
+    xml = @contact.to_xml root: 'xml_contact', camelize: true
+    assert_match %r{^<XmlContact>},  xml
+    assert_match %r{</XmlContact>$}, xml
+    assert_match %r{<CreatedAt},     xml
   end
 
   test "should allow lower-camelized tags" do
-    @xml = @contact.to_xml root: 'xml_contact', camelize: :lower
-    assert_match %r{^<xmlContact>},  @xml
-    assert_match %r{</xmlContact>$}, @xml
-    assert_match %r{<createdAt},     @xml
+    xml = @contact.to_xml root: 'xml_contact', camelize: :lower
+    assert_match %r{^<xmlContact>},  xml
+    assert_match %r{</xmlContact>$}, xml
+    assert_match %r{<createdAt},     xml
   end
 
   test "should use serializable hash" do
@@ -106,22 +106,22 @@ class XmlSerializationTest < ActiveModel::TestCase
     @contact.name = 'aaron stack'
     @contact.age = 25
 
-    @xml = @contact.to_xml
-    assert_match %r{<name>aaron stack</name>}, @xml
-    assert_match %r{<age type="integer">25</age>}, @xml
-    assert_no_match %r{<awesome>}, @xml
+    xml = @contact.to_xml
+    assert_match %r{<name>aaron stack</name>}, xml
+    assert_match %r{<age type="integer">25</age>}, xml
+    assert_no_match %r{<awesome>}, xml
   end
 
   test "should allow skipped types" do
-    @xml = @contact.to_xml skip_types: true
-    assert_match %r{<age>25</age>}, @xml
+    xml = @contact.to_xml skip_types: true
+    assert_match %r{<age>25</age>}, xml
   end
 
   test "should include yielded additions" do
-    @xml = @contact.to_xml do |xml|
+    xml = @contact.to_xml do |xml|
       xml.creator "David"
     end
-    assert_match %r{<creator>David</creator>}, @xml
+    assert_match %r{<creator>David</creator>}, xml
   end
 
   test "should serialize string" do
@@ -162,7 +162,7 @@ class XmlSerializationTest < ActiveModel::TestCase
     assert_match %r{<nationality>unknown</nationality>}, xml
   end
 
-  test 'should supply serializable to second proc argument' do
+  test "should supply serializable to second proc argument" do
     proc = Proc.new { |options, record| options[:builder].tag!('name-reverse', record.name.reverse) }
     xml = @contact.to_xml(procs: [ proc ])
     assert_match %r{<name-reverse>kcats noraa</name-reverse>}, xml
diff --git a/activemodel/test/cases/validations/confirmation_validation_test.rb b/activemodel/test/cases/validations/confirmation_validation_test.rb
index 4c3d7a7615..65a2a1eb49 100644
--- a/activemodel/test/cases/validations/confirmation_validation_test.rb
+++ b/activemodel/test/cases/validations/confirmation_validation_test.rb
@@ -53,17 +53,17 @@ class ConfirmationValidationTest < ActiveModel::TestCase
   end
 
   def test_title_confirmation_with_i18n_attribute
-    @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
-    I18n.load_path.clear
-    I18n.backend = I18n::Backend::Simple.new
-    I18n.backend.store_translations('en', {
-      errors: { messages: { confirmation: "doesn't match %{attribute}" } },
-      activemodel: { attributes: { topic: { title: 'Test Title'} } }
-    })
+    begin
+      @old_load_path, @old_backend = I18n.load_path.dup, I18n.backend
+      I18n.load_path.clear
+      I18n.backend = I18n::Backend::Simple.new
+      I18n.backend.store_translations('en', {
+        errors: { messages: { confirmation: "doesn't match %{attribute}" } },
+        activemodel: { attributes: { topic: { title: 'Test Title'} } }
+      })
 
-    Topic.validates_confirmation_of(:title)
+      Topic.validates_confirmation_of(:title)
 
-    begin
       t = Topic.new("title" => "We should be confirmed","title_confirmation" => "")
       assert t.invalid?
       assert_equal ["doesn't match Test Title"], t.errors[:title_confirmation]
diff --git a/activemodel/test/cases/validations/numericality_validation_test.rb b/activemodel/test/cases/validations/numericality_validation_test.rb
index f77cf47fb7..e1657407cf 100644
--- a/activemodel/test/cases/validations/numericality_validation_test.rb
+++ b/activemodel/test/cases/validations/numericality_validation_test.rb
@@ -119,6 +119,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
 
     invalid!([3, 4])
     valid!([5, 6])
+  ensure
     Topic.send(:remove_method, :min_approved)
   end
 
@@ -128,6 +129,7 @@ class NumericalityValidationTest < ActiveModel::TestCase
 
     invalid!([6])
     valid!([4, 5])
+  ensure
     Topic.send(:remove_method, :max_approved)
   end
 
diff --git a/activemodel/test/cases/validations_test.rb b/activemodel/test/cases/validations_test.rb
index cfce8fb8e6..4ea5670d32 100644
--- a/activemodel/test/cases/validations_test.rb
+++ b/activemodel/test/cases/validations_test.rb
@@ -139,6 +139,8 @@ class ValidationsTest < ActiveModel::TestCase
     assert_equal 4, hits
     assert_equal %w(gotcha gotcha), t.errors[:title]
     assert_equal %w(gotcha gotcha), t.errors[:content]
+  ensure
+    CustomReader.clear_validators!
   end
 
   def test_validate_block