When parameters define file name and extension delimited by `.`, can not generate expectedly.

### Example

`routes.rb`
```ruby
    get    '/test/:filename.:extension'                               => 'test#show', as: :test
```

`rails-routes.ts`
```ts
export function testPath(params: Params<'filename.:extension' | 'extension + ''>) { return process('/test/' + params.filename.' + params.extension + ' + '', params, ['filename.:extension','extension + '']); }
```