Smarty Debug triggers undefined array key warnings

[jakoch]

Smarty v5.5.2 triggers the following warnings:

vendor/smarty/smarty/src/Debug.php:107
Undefined array key "compile_time"

vendor/smarty/smarty/src/Debug.php:130
Undefined array key "render_time"

• https://github.com/smarty-php/smarty/blob/v5.5.2/src/Debug.php#L107
• https://github.com/smarty-php/smarty/blob/v5.5.2/src/Debug.php#L130

The fix is to predefine the keys in $template_data array, e.g.

        if(!array_key_exists('render_time', $this->template_data[ $this->index ][ $key ])) {
            $this->template_data[ $this->index ][ $key ][ 'render_time' ] = 0;
        }