diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 26f821750b9..0cf452d683c 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -5159,7 +5159,7 @@ function price2num($amount, $rounding = '', $option = 0)
 
 	// Convert value to universal number format (no thousand separator, '.' as decimal separator)
 	if ($option != 1) {	// If not a PHP number or unknown, we change or clean format
-		//print 'PP'.$amount.' - '.$dec.' - '.$thousand.' - '.intval($amount).'<br>';
+		//print "\n".'PP'.$amount.' - '.$dec.' - '.$thousand.' - '.intval($amount).'<br>';
 		if (!is_numeric($amount)) {
 			$amount = preg_replace('/[a-zA-Z\/\\\*\(\)\<\>\_]/', '', $amount);
 		}
@@ -5188,6 +5188,7 @@ function price2num($amount, $rounding = '', $option = 0)
 		$amount = str_replace($thousand, '', $amount); // Replace of thousand before replace of dec to avoid pb if thousand is .
 		$amount = str_replace($dec, '.', $amount);
 	}
+	//print ' XX'.$amount.' '.$rounding;
 
 	// Now, make a rounding if required
 	if ($rounding) {
@@ -5205,13 +5206,13 @@ function price2num($amount, $rounding = '', $option = 0)
 		} elseif (is_numeric($rounding)) {
 			$nbofdectoround = (int) $rounding;
 		}
-		//print "RR".$amount.' - '.$nbofdectoround.'<br>';
+		//print " RR".$amount.' - '.$nbofdectoround.'<br>';
 		if (dol_strlen($nbofdectoround)) {
 			$amount = round(is_string($amount) ? (float) $amount : $amount, $nbofdectoround); // $nbofdectoround can be 0.
 		} else {
 			return 'ErrorBadParameterProvidedToFunction';
 		}
-		//print 'SS'.$amount.' - '.$nbofdec.' - '.$dec.' - '.$thousand.' - '.$nbofdectoround.'<br>';
+		//print ' SS'.$amount.' - '.$nbofdec.' - '.$dec.' - '.$thousand.' - '.$nbofdectoround.'<br>';
 
 		// Convert amount to format with dolibarr dec and thousand (this is because PHP convert a number
 		// to format defined by LC_NUMERIC after a calculation and we want source format to be defined by Dolibarr setup.
diff --git a/test/phpunit/FunctionsLibTest.php b/test/phpunit/FunctionsLibTest.php
index f1341c9a042..e43453b26ec 100644
--- a/test/phpunit/FunctionsLibTest.php
+++ b/test/phpunit/FunctionsLibTest.php
@@ -108,7 +108,15 @@ class FunctionsLibTest extends PHPUnit\Framework\TestCase
 		//$db->begin();	// This is to have all actions inside a transaction even if test launched without suite.
 
 		if (! function_exists('mb_substr')) {
-			print "\n".__METHOD__." function mb_substr must be enabled.\n"; die();
+			print "\n".__METHOD__." function mb_substr must be enabled.\n"; die(1);
+		}
+
+		if ($conf->global->MAIN_MAX_DECIMALS_UNIT != 5) {
+			print "\n".__METHOD__." bad setup for number of digits for unit amount. Must be 5 for this test.\n"; die(1);
+		}
+
+		if ($conf->global->MAIN_MAX_DECIMALS_TOT != 2) {
+			print "\n".__METHOD__." bad setup for number of digits for unit amount. Must be 2 for this test.\n"; die(1);
 		}
 
 		print __METHOD__."\n";
@@ -1294,7 +1302,7 @@ class FunctionsLibTest extends PHPUnit\Framework\TestCase
 		$this->assertEquals(1000.123456, price2num('1 000.123456'));
 
 		// Round down
-		$this->assertEquals(1000.12, price2num('1 000.123452', 'MT'));
+		$this->assertEquals(1000.12, price2num('1 000.123452', 'MT'), 'Error in round down with MT');
 		$this->assertEquals(1000.12345, price2num('1 000.123452', 'MU'), "Test MU");
 
 		// Round up