diff --git a/activemodel/test/cases/mass_assignment_security/sanitizer_test.rb b/activemodel/test/cases/mass_assignment_security/sanitizer_test.rb
index 367207aab3..015153ec7c 100644
--- a/activemodel/test/cases/mass_assignment_security/sanitizer_test.rb
+++ b/activemodel/test/cases/mass_assignment_security/sanitizer_test.rb
@@ -31,7 +31,7 @@ class SanitizerTest < ActiveModel::TestCase
     log = StringIO.new
     @sanitizer.logger = Logger.new(log)
     @sanitizer.sanitize(original_attributes)
-    assert (log.string =~ /admin/), "Should log removed attributes: #{log.string}"
+    assert_match(/admin/, log.string, "Should log removed attributes: #{log.string}")
   end
 
 end
diff --git a/activemodel/test/cases/mass_assignment_security_test.rb b/activemodel/test/cases/mass_assignment_security_test.rb
index 0f7a38b0bc..c25b0fdf00 100644
--- a/activemodel/test/cases/mass_assignment_security_test.rb
+++ b/activemodel/test/cases/mass_assignment_security_test.rb
@@ -35,10 +35,10 @@ class MassAssignmentSecurityTest < ActiveModel::TestCase
     assert_equal Set.new([ 'credit_rating', 'administrator', 'phone_number', 'name']), LooseDescendantSecond.protected_attributes,
       'Running attr_protected twice in one class should merge the protections'
 
-    assert (TightPerson.protected_attributes - TightPerson.attributes_protected_by_default).blank?
+    assert_blank TightPerson.protected_attributes - TightPerson.attributes_protected_by_default
     assert_equal Set.new([ 'name', 'address' ]), TightPerson.accessible_attributes
 
-    assert (TightDescendant.protected_attributes - TightDescendant.attributes_protected_by_default).blank?
+    assert_blank TightDescendant.protected_attributes - TightDescendant.attributes_protected_by_default
     assert_equal Set.new([ 'name', 'address', 'phone_number' ]), TightDescendant.accessible_attributes
   end
 
@@ -49,4 +49,4 @@ class MassAssignmentSecurityTest < ActiveModel::TestCase
     assert_equal sanitized, { }
   end
 
-end
\ No newline at end of file
+end