Filter scalar values when params permit hashes or arrays

This brings the behavior more inline with other similar cases, such as
receiving a hash when an array of scalars was expected. Prior to this
commit, the key would be present, but the value would be `nil`

1 files changed, 9 insertions, 0 deletions

diff --git a/actionpack/test/controller/parameters/parameters_permit_test.rb b/actionpack/test/controller/parameters/parameters_permit_test.rb
index 96048e2868..b75eb0e3bf 100644
--- a/actionpack/test/controller/parameters/parameters_permit_test.rb
+++ b/actionpack/test/controller/parameters/parameters_permit_test.rb
@@ -360,4 +360,13 @@ class ParametersPermitTest < ActiveSupport::TestCase
     assert @params.include? 'person'
     assert_not @params.include? :gorilla
   end
+
+  test "scalar values should be filtered when array or hash is specified" do
+    params = ActionController::Parameters.new(foo: "bar")
+
+    assert params.permit(:foo).has_key?(:foo)
+    refute params.permit(foo: []).has_key?(:foo)
+    refute params.permit(foo: [:bar]).has_key?(:foo)
+    refute params.permit(foo: :bar).has_key?(:foo)
+  end
 end