Smarty Debug triggers undefined array key warnings

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;
        }

Start in src/Debug.php at lines 107 and 130, where the issue reports undefined array key warnings for compile_time and render_time. Reproduce the Smarty Debug behavior and inspect how template_data is populated. Done means those warnings no longer occur when the debug data lacks either key.