From 17c61088324390a285dfd5d76fc37d6399441be1 Mon Sep 17 00:00:00 2001
From: Manos Psychogyiopoulos <psyx@somewherewarm.net>
Date: Thu, 21 Jul 2016 12:14:12 +0300
Subject: [PATCH] ensure WC_ROUNDING_PRECISION is defined and use it as a low
 precision boundary in wc_get_rounding_precision()

---
 includes/wc-core-functions.php       | 11 ++++++-----
 tests/unit-tests/util/main-class.php |  1 +
 woocommerce.php                      |  1 +
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/includes/wc-core-functions.php b/includes/wc-core-functions.php
index 89ef6103158..0f930042a39 100644
--- a/includes/wc-core-functions.php
+++ b/includes/wc-core-functions.php
@@ -1355,15 +1355,16 @@ function wc_product_attribute_uasort_comparison( $a, $b ) {
 }
 
 /**
- * Get rounding precision.
+ * Get rounding precision for internal WC calculations.
+ * Will increase the precision of wc_get_price_decimals by 2 decimals, unless WC_ROUNDING_PRECISION is set to a higher number.
  *
  * @since 2.6.3
  * @return int
  */
 function wc_get_rounding_precision() {
-	if ( defined( 'WC_ROUNDING_PRECISION' ) ) {
-		return absint( WC_ROUNDING_PRECISION );
+	$precision = wc_get_price_decimals() + 2;
+	if ( absint( WC_ROUNDING_PRECISION ) > $precision ) {
+		$precision = absint( WC_ROUNDING_PRECISION );
 	}
-
-	return wc_get_price_decimals() + 2;
+	return $precision;
 }
diff --git a/tests/unit-tests/util/main-class.php b/tests/unit-tests/util/main-class.php
index b3d969aac4d..e525c9b9ad4 100644
--- a/tests/unit-tests/util/main-class.php
+++ b/tests/unit-tests/util/main-class.php
@@ -46,6 +46,7 @@ class WC_Tests_Main_Class extends WC_Unit_Test_Case {
 
 		$this->assertEquals( $this->wc->version, WC_VERSION );
 		$this->assertEquals( WC_VERSION, WOOCOMMERCE_VERSION );
+		$this->assertEquals( 4, WC_ROUNDING_PRECISION );
 		$this->assertContains( WC_TAX_ROUNDING_MODE, array( 2, 1 ) );
 		$this->assertEquals( '|', WC_DELIMITER );
 		$this->assertNotEquals( WC_LOG_DIR, '' );
diff --git a/woocommerce.php b/woocommerce.php
index 5b0f338315e..124fc2edaf1 100644
--- a/woocommerce.php
+++ b/woocommerce.php
@@ -181,6 +181,7 @@ final class WooCommerce {
 		$this->define( 'WC_PLUGIN_BASENAME', plugin_basename( __FILE__ ) );
 		$this->define( 'WC_VERSION', $this->version );
 		$this->define( 'WOOCOMMERCE_VERSION', $this->version );
+		$this->define( 'WC_ROUNDING_PRECISION', 4 );
 		$this->define( 'WC_DISCOUNT_ROUNDING_MODE', 2 );
 		$this->define( 'WC_TAX_ROUNDING_MODE', 'yes' === get_option( 'woocommerce_prices_include_tax', 'no' ) ? 2 : 1 );
 		$this->define( 'WC_DELIMITER', '|' );