From 17076a1e4795c0290ffc4aa8c43e2fac9f8f399b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tanguy=20Ch=C3=A9nier?=
 <22911157+tanguychenier@users.noreply.github.com>
Date: Mon, 15 Jun 2026 14:18:44 +0200
Subject: [PATCH] FIX Stock balance truncated to int for fractional qty
 (#38806)

calculateBalanceForProductBefore() cast the SUM of stock movement values
to (int), which truncated the fractional part. For products tracked in
fractional units (kg, liters, ...), the before/after period stock balance
displayed in the stock movement list (product/stock/movement_list.php) was
wrong (for example a real balance of 10.5 was shown as 10).

Cast the computed balance to (float) instead and update the method return
type accordingly.

Add a PHPUnit test (MouvementStockTest::testCalculateBalanceForProductBefore)
that records a fractional reception and checks the returned balance is not
truncated.
---
 .../stock/class/mouvementstock.class.php      |  4 +-
 test/phpunit/MouvementStockTest.php           | 40 +++++++++++++++++++
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/htdocs/product/stock/class/mouvementstock.class.php b/htdocs/product/stock/class/mouvementstock.class.php
index 05a70765b4a..58d22729166 100644
--- a/htdocs/product/stock/class/mouvementstock.class.php
+++ b/htdocs/product/stock/class/mouvementstock.class.php
@@ -900,7 +900,7 @@ class MouvementStock extends CommonObject
 	 *
 	 * @param 	int			$productidselected		Id of product to count
 	 * @param 	integer 	$datebefore				Date limit
-	 * @return	int			Number
+	 * @return	float		Number
 	 */
 	public function calculateBalanceForProductBefore($productidselected, $datebefore)
 	{
@@ -915,7 +915,7 @@ class MouvementStock extends CommonObject
 		if ($resql) {
 			$obj = $this->db->fetch_object($resql);
 			if ($obj) {
-				$nb = (int) $obj->nb;
+				$nb = (float) $obj->nb;
 			}
 			return (empty($nb) ? 0 : $nb);
 		} else {
diff --git a/test/phpunit/MouvementStockTest.php b/test/phpunit/MouvementStockTest.php
index 6e61b203ce8..4a23d2df855 100644
--- a/test/phpunit/MouvementStockTest.php
+++ b/test/phpunit/MouvementStockTest.php
@@ -48,6 +48,10 @@ $conf->global->MAIN_DISABLE_ALL_MAILS = 1;
  * @backupGlobals disabled
  * @backupStaticAttributes enabled
  * @remarks	backupGlobals must be disabled to have db,conf,user and lang not erased.
+ * @phan-file-suppress PhanUndeclaredClass
+ * @phan-file-suppress PhanUndeclaredExtendedClass
+ * @phan-file-suppress PhanUndeclaredMethod
+ * @phan-file-suppress PhanUndeclaredProperty
  */
 class MouvementStockTest extends CommonClassTest
 {
@@ -239,4 +243,40 @@ class MouvementStockTest extends CommonClassTest
 
 		return $localobject;
 	}
+
+	/**
+	 * testCalculateBalanceForProductBefore
+	 *
+	 * @return	void
+	 */
+	public function testCalculateBalanceForProductBefore()
+	{
+		global $conf,$user,$langs,$db;
+		$conf = $this->savconf;
+		$user = $this->savuser;
+		$langs = $this->savlangs;
+		$db = $this->savdb;
+
+		$product = new Product($db);
+		$product->initAsSpecimen();
+		$product->ref .= ' phpunit balance';
+		$product->label .= ' phpunit balance';
+		$productid = $product->create($user);
+		$this->assertGreaterThan(0, $productid, 'Failed to create product');
+
+		$warehouse = new Entrepot($db);
+		$warehouse->initAsSpecimen();
+		$warehouse->label .= ' phpunit balance';
+		$warehouseid = $warehouse->create($user);
+		$this->assertGreaterThan(0, $warehouseid, 'Failed to create warehouse');
+
+		$movement = new MouvementStock($db);
+		$movementdate = dol_mktime(0, 0, 0, 1, 1, 2020);
+		$result = $movement->reception($user, $productid, $warehouseid, 2.5, 0, 'Fractional qty for unit test', '', '', '', $movementdate, 0, 'Inventory Code Balance');
+		$this->assertGreaterThan(0, $result, 'Failed to create fractional stock movement');
+
+		$balance = $movement->calculateBalanceForProductBefore($productid, dol_now());
+		print __METHOD__." balance=".$balance."\n";
+		$this->assertEquals(2.5, $balance, 'Fractional stock balance must not be truncated to an integer');
+	}
 }