6 files changed, 36 insertions, 25 deletions
diff --git a/actionmailer/test/base_test.rb b/actionmailer/test/base_test.rb
index 4ed332d13d..fcf5be56f7 100644
--- a/actionmailer/test/base_test.rb
+++ b/actionmailer/test/base_test.rb
@@ -493,14 +493,18 @@ class BaseTest < ActiveSupport::TestCase
   end
 
   test "assets tags should use a Mailer's asset_host settings when available" do
-    ActionMailer::Base.config.asset_host = "global.com"
-    ActionMailer::Base.config.assets_dir = "global/"
+    begin
+      ActionMailer::Base.config.asset_host = "http://global.com"
+      ActionMailer::Base.config.assets_dir = "global/"
 
-    AssetMailer.asset_host = "http://local.com"
+      AssetMailer.asset_host = "http://local.com"
 
-    mail = AssetMailer.welcome
+      mail = AssetMailer.welcome
 
-    assert_equal(%{<img alt="Dummy" src="http://local.com/images/dummy.png" />}, mail.body.to_s.strip)
+      assert_equal(%{<img alt="Dummy" src="http://local.com/images/dummy.png" />}, mail.body.to_s.strip)
+    ensure
+      AssetMailer.asset_host = ActionMailer::Base.config.asset_host
+    end
   end
 
   # Before and After hooks
diff --git a/activemodel/test/cases/mass_assignment_security_test.rb b/activemodel/test/cases/mass_assignment_security_test.rb
index 0c6352cd71..45757615f5 100644
--- a/activemodel/test/cases/mass_assignment_security_test.rb
+++ b/activemodel/test/cases/mass_assignment_security_test.rb
@@ -11,7 +11,6 @@ class CustomSanitizer < ActiveModel::MassAssignmentSecurity::Sanitizer
 end
 
 class MassAssignmentSecurityTest < ActiveModel::TestCase
-
   def test_attribute_protection
     user = User.new
     expected = { "name" => "John Smith", "email" => "john@smith.com" }
@@ -96,7 +95,6 @@ class MassAssignmentSecurityTest < ActiveModel::TestCase
 
     assert_blank TightDescendant.protected_attributes(:admin) - TightDescendant.attributes_protected_by_default
     assert_equal Set.new(['name', 'address', 'admin', 'super_powers']), TightDescendant.accessible_attributes(:admin)
-
   end
 
   def test_mass_assignment_multiparameter_protector
@@ -107,14 +105,14 @@ class MassAssignmentSecurityTest < ActiveModel::TestCase
   end
 
   def test_custom_sanitizer
+    old_sanitizer = User._mass_assignment_sanitizer
+
     user = User.new
     User.mass_assignment_sanitizer = CustomSanitizer.new
     assert_raise StandardError do
       user.sanitize_for_mass_assignment("admin" => true)
     end
   ensure
-    User.mass_assignment_sanitizer = nil
-
+    User.mass_assignment_sanitizer = old_sanitizer
   end
-
-end
+end
+\ No newline at end of file
diff --git a/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb b/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
index ef66ddaac7..402609c583 100644
--- a/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
+++ b/activesupport/test/autoloading_fixtures/class_folder/class_folder_subclass.rb
@@ -1,3 +1,3 @@
 class ClassFolder::ClassFolderSubclass < ClassFolder
-  ConstantInClassFolder
+  ConstantInClassFolder = 'indeed'
 end
diff --git a/activesupport/test/core_ext/module/qualified_const_test.rb b/activesupport/test/core_ext/module/qualified_const_test.rb
index 8af0b9a023..343a848a42 100644
--- a/activesupport/test/core_ext/module/qualified_const_test.rb
+++ b/activesupport/test/core_ext/module/qualified_const_test.rb
@@ -67,17 +67,24 @@ class QualifiedConstTest < ActiveSupport::TestCase
   end
 
   test "qualified_const_set" do
-    m = Module.new
-    assert_equal m, Object.qualified_const_set("QualifiedConstTestMod2", m)
-    assert_equal m, ::QualifiedConstTestMod2
-
-    # We are going to assign to existing constants on purpose, so silence warnings.
-    silence_warnings do
-      assert_equal true, QualifiedConstTestMod.qualified_const_set("QualifiedConstTestMod::X", true)
-      assert_equal true, QualifiedConstTestMod::X
-
-      assert_equal 10, QualifiedConstTestMod::M.qualified_const_set("X", 10)
-      assert_equal 10, QualifiedConstTestMod::M::X
+    begin
+      m = Module.new
+      assert_equal m, Object.qualified_const_set("QualifiedConstTestMod2", m)
+      assert_equal m, ::QualifiedConstTestMod2
+
+      # We are going to assign to existing constants on purpose, so silence warnings.
+      silence_warnings do
+        assert_equal true, QualifiedConstTestMod.qualified_const_set("QualifiedConstTestMod::X", true)
+        assert_equal true, QualifiedConstTestMod::X
+
+        assert_equal 10, QualifiedConstTestMod::M.qualified_const_set("X", 10)
+        assert_equal 10, QualifiedConstTestMod::M::X
+      end
+    ensure
+      silence_warnings do
+        QualifiedConstTestMod.qualified_const_set('QualifiedConstTestMod::X', false)
+        QualifiedConstTestMod::M.qualified_const_set('X', 1)
+      end
     end
   end
 
diff --git a/activesupport/test/dependencies_test.rb b/activesupport/test/dependencies_test.rb
index 69829bcda5..f1da6378a7 100644
--- a/activesupport/test/dependencies_test.rb
+++ b/activesupport/test/dependencies_test.rb
@@ -679,6 +679,8 @@ class DependenciesTest < ActiveSupport::TestCase
       assert_equal true, M.unloadable
       assert_equal false, M.unloadable
     end
+  ensure
+    Object.class_eval { remove_const :M }
   end
 
   def test_unloadable_constants_should_receive_callback
diff --git a/activesupport/test/inflector_test.rb b/activesupport/test/inflector_test.rb
index cd91002147..aa41e57928 100644
--- a/activesupport/test/inflector_test.rb
+++ b/activesupport/test/inflector_test.rb
@@ -169,11 +169,11 @@ class InflectorTest < ActiveSupport::TestCase
   def test_underscore_acronym_sequence
     ActiveSupport::Inflector.inflections do |inflect|
       inflect.acronym("API")
-      inflect.acronym("HTML5")
+      inflect.acronym("JSON")
       inflect.acronym("HTML")
     end
 
-    assert_equal("html5_html_api", ActiveSupport::Inflector.underscore("HTML5HTMLAPI"))
+    assert_equal("json_html_api", ActiveSupport::Inflector.underscore("JSONHTMLAPI"))
   end
 
   def test_underscore