Helper/Cart.php
public function isCheckoutAllowed()
    {
        return $this->customerSession->isLoggedIn() || $this->checkoutHelper->isAllowedGuestCheckout($this->checkoutSession->getQuote());
    }
public function isCheckoutAllowed()
    {
        return $this->customerSession->isLoggedIn() || $this->checkoutHelper->isAllowedGuestCheckout($this->checkoutSession->getQuote());
    }
public function isCheckoutAllowed ( ) { return $ this -> customerSession -> isLoggedIn ( ) || $ this -> checkoutHelper -> isAllowedGuestCheckout ( $ this -> checkoutSession -> getQuote ( ) ) ; }
Check if guest checkout is allowed

@return bool
Check if guest checkout is allowed