app/Subscriptions/Plans.php
public function find($id)
    {
        foreach ($this->plans as $plan) {
            if ($plan->id === $id) {
                return $plan;
            }
        }

        throw new Exception("Unable to find plan with ID [{$id}].");
    }
public function find($id)
    {
        foreach ($this->plans as $plan) {
            if ($plan->id === $id) {
                return $plan;
            }
        }

        throw new Exception("Unable to find plan with ID [{$id}].");
    }
Get plan matching a given ID.

@param  string  $id
@return \Laravel\Spark\Subscriptions\Plan