Check coupons are valid before cart/checkout

classes/class-wc-cart.php

@@ -51,6 +51,7 @@ class WC_Cart {
 		$this->get_cart_from_session();
 		
 		add_action('woocommerce_check_cart_items', array(&$this, 'check_cart_items'), 1);
+		add_action('woocommerce_check_cart_items', array(&$this, 'check_cart_coupons'), 1);
 		add_action('woocommerce_after_checkout_validation', array(&$this, 'check_customer_coupons'), 1);
     }
 
@@ -231,6 +232,29 @@ class WC_Cart {
 				$woocommerce->add_error( $result->get_error_message() );
 		}
 		
+		/**
+		 * Check cart coupons for errors
+		 */
+		function check_cart_coupons() {
+			global $woocommerce;
+			
+			if ( ! empty( $this->applied_coupons ) ) {
+				foreach ( $this->applied_coupons as $key => $code ) {
+					$coupon = new WC_Coupon( $code );
+					
+					if ( is_wp_error( $coupon->is_valid() ) ) {
+						
+						$woocommerce->add_error( sprintf( __('Sorry, it seems the coupon "%s" is invalid - it has now been removed from your order.', 'woocommerce'), $code ) );
+						
+						// Remove the coupon
+						unset( $this->applied_coupons[$key] );
+						$_SESSION['coupons'] = $this->applied_coupons;
+						$_SESSION['refresh_totals'] = true;
+					}
+				}
+			}
+		}
+		
 		/**
 		 * Get cart items quantities - merged so we can do accurate stock checks
 		 * 

classes/class-wc-coupon.php

@@ -215,7 +215,8 @@ class WC_Coupon {
 			
 			$valid = apply_filters( 'woocommerce_coupon_is_valid', $valid, $this );
 			
-			if ( $valid ) return true;
+			if ( $valid ) 
+				return true;
 		
 		endif;
 		

classes/class-wc-product.php

@@ -944,7 +944,7 @@ class WC_Product {
 	/** Depreciated - naming was confusing */
 	function get_available_attribute_variations() {
 		_deprecated_function( 'get_available_attribute_variations', '1.5.7', 'get_variation_attributes' );
-		$this->get_variation_attributes();
+		return $this->get_variation_attributes();
 	}
 
     /**

readme.txt

@@ -193,6 +193,7 @@ Yes you can! Join in on our [GitHub repository](http://github.com/woothemes/wooc
 * Tweak - Exempt from VAT shows price ex VAT
 * Tweak - Newlines for order meta (flat)
 * Tweak - Show method title when free
+* Fix - check_cart_coupons on checkout to prevent invalid coupons being used
 * Fix - Hide out of stock now works with widgets.
 * Fix - Strange error where detecting the page (is_page etc) would break the canonical redirect in some instances when hooked into 'wp'. Used the later get_header hook instead.
 * Fix - Right now links.

shortcodes/shortcode-cart.php

@@ -70,11 +70,12 @@ function woocommerce_cart( $atts ) {
 
 	}
 	
+	// Check cart items are valid
+	do_action('woocommerce_check_cart_items');
+	
 	// Calc totals
 	$woocommerce->cart->calculate_totals();
 	
-	do_action('woocommerce_check_cart_items');
-	
 	if (sizeof($woocommerce->cart->get_cart())==0) :
 		
 		woocommerce_get_template( 'cart/empty.php' );