diff --git a/lib/devise/models/confirmable.rb b/lib/devise/models/confirmable.rb
index f323d454..e6df31ac 100644
--- a/lib/devise/models/confirmable.rb
+++ b/lib/devise/models/confirmable.rb
@@ -56,7 +56,7 @@ module Devise
       # Confirm a user by setting it's confirmed_at to actual time. If the user
       # is already confirmed, add an error to email field. If the user is invalid
       # add errors
-      def confirm!(ensure_valid=false)
+      def confirm!(ensure_valid: false)
         pending_any_confirmation do
           if confirmation_period_expired?
             self.errors.add(:email, :confirmation_period_expired,
diff --git a/test/models/confirmable_test.rb b/test/models/confirmable_test.rb
index 0c2c56ff..10cd160d 100644
--- a/test/models/confirmable_test.rb
+++ b/test/models/confirmable_test.rb
@@ -315,6 +315,12 @@ class ConfirmableTest < ActiveSupport::TestCase
     assert_not user.confirm!
     assert_equal user.username, old
   end
+
+  test 'should always perform validations upon confirm when ensure valid true' do
+    admin = create_admin
+    admin.stubs(:valid?).returns(false)
+    assert_not admin.confirm!(ensure_valid: true)
+  end
 end
 
 class ReconfirmableTest < ActiveSupport::TestCase