StackFormation\DependencyTracker::getUsedEnvironmentVariables PHP Method

    public function getUsedEnvironmentVariables()
    {
        $vars = [];
        foreach ($this->envVars as $type => $typeData) {
            foreach ($typeData as $variableName => $data) {
                $vars[$variableName] = $data['value'];
            }
        }
        ksort($vars);
        return $vars;
    }