From eb3b1dbee6613c54d35c53b3f5ce6bd2a6340c95 Mon Sep 17 00:00:00 2001
From: Mike Jolley <mike.jolley@me.com>
Date: Wed, 11 Apr 2018 13:19:39 +0100
Subject: [PATCH] Add dummy product to cart when viewing preview

---
 includes/class-wc-cart-session.php            |  4 +++
 .../customizer/class-wc-shop-customizer.php   | 26 +++++++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/includes/class-wc-cart-session.php b/includes/class-wc-cart-session.php
index 668c6e1acb6..ed9d87acf09 100644
--- a/includes/class-wc-cart-session.php
+++ b/includes/class-wc-cart-session.php
@@ -97,6 +97,10 @@ final class WC_Cart_Session {
 			foreach ( $cart as $key => $values ) {
 				$product = wc_get_product( $values['variation_id'] ? $values['variation_id'] : $values['product_id'] );
 
+				if ( ! is_customize_preview() && 'customize-preview' === $key ) {
+					continue;
+				}
+
 				if ( ! empty( $product ) && $product->exists() && $values['quantity'] > 0 ) {
 
 					if ( ! $product->is_purchasable() ) {
diff --git a/includes/customizer/class-wc-shop-customizer.php b/includes/customizer/class-wc-shop-customizer.php
index 84e18369918..9fb9a00861d 100644
--- a/includes/customizer/class-wc-shop-customizer.php
+++ b/includes/customizer/class-wc-shop-customizer.php
@@ -21,6 +21,7 @@ class WC_Shop_Customizer {
 		add_action( 'customize_controls_print_styles', array( $this, 'add_styles' ) );
 		add_action( 'customize_controls_print_scripts', array( $this, 'add_scripts' ), 30 );
 		add_action( 'wp_enqueue_scripts', array( $this, 'add_frontend_scripts' ) );
+		add_action( 'woocommerce_cart_loaded_from_session', array( $this, 'populate_cart' ) );
 	}
 
 	/**
@@ -54,6 +55,31 @@ class WC_Shop_Customizer {
 		wp_add_inline_style( 'customize-preview', $css );
 	}
 
+	/**
+	 * Make sure the cart has something inside when we're customizing.
+	 *
+	 * @return void
+	 */
+	public function populate_cart() {
+		if ( ! is_customize_preview() ) {
+			return;
+		}
+		if ( WC()->cart->is_empty() ) {
+			$dummy_product = new WC_Product();
+			$dummy_product->set_name( 'Sample' );
+			$dummy_product->set_price( 0 );
+			$dummy_product->set_status( 'publish' );
+			$cart_contents['customize-preview'] = array(
+				'data'         => $dummy_product,
+				'product_id'   => 0,
+				'variation_id' => 0,
+				'data_hash'    => false,
+				'quantity'     => 1,
+			);
+			WC()->cart->set_cart_contents( $cart_contents );
+		}
+	}
+
 	/**
 	 * CSS styles to improve our form.
 	 */