Using a number as a nested key breaks permit

[anthonator]

I ran into an issue today with nested numbers as keys breaking permit. It only breaks if the key is nested. If it's a top-level key it works just fine.

I'm using Rails 4.2.6 and Ruby 2.3.0.

Examples:

broken

params = ActionController::Parameters.new(photos: { '1' => { 'hello': 'world' } })
params.permit(photos: { '1' => [:hello] }) # => {"photos"=>{"1"=>{}}}

works

params = ActionController::Parameters.new('1' => { 'hello': 'world' })
params.permit('1' => ['hello']) # => {"1" => { "hello": "world" }}

params = ActionController::Parameters.new(photos: { 'key_1' => { 'hello': 'world' } })
params.permit(photos: { 'key_1' => [:hello] }) # => {"photos"=>{"key_1"=>{"hello"=>"world"}}}

Of course renaming your keys is the easy workaround. Just thought I'd create some documentation around the issue.