From a4a4ebe95c2cc37ca57b40b64b4d3aee22cdbf97 Mon Sep 17 00:00:00 2001
From: Yurii Myronchuk <bladeroot@gmail.com>
Date: Tue, 22 Apr 2025 14:32:58 +0000
Subject: [PATCH 1/2] HP-2446: format number as string

---
 src/price/ProgressivePrice.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/price/ProgressivePrice.php b/src/price/ProgressivePrice.php
index baabf712..6c355e19 100644
--- a/src/price/ProgressivePrice.php
+++ b/src/price/ProgressivePrice.php
@@ -105,8 +105,8 @@ public function calculateSum(QuantityInterface $quantity): ?Money
             $price = $threshold->price();
 
             $chargedAmount = $price->money()
-                                   ->multiply((string)$billedUsage->getQuantity())
-                                   ->divide((string)($price->multiplier()));
+                                   ->multiply((string)(sprintf('%.14F', $billedUsage->getQuantity())))
+                                   ->divide((string)(sprintf('%.14F', $price->multiplier())));
 
             $this->calculationTraces[] = new ProgressivePriceCalculationTrace(
                 $threshold, $billedUsage, $chargedAmount

From b8a622b0c40225bbd9e57f5cc5f57d0242f758f3 Mon Sep 17 00:00:00 2001
From: Yurii Myronchuk <bladeroot@gmail.com>
Date: Tue, 6 May 2025 17:12:39 +0000
Subject: [PATCH 2/2] Fix test

---
 tests/unit/price/ProgressivePriceTest.php | 37 +++++++++++++++++++++++
 1 file changed, 37 insertions(+)

diff --git a/tests/unit/price/ProgressivePriceTest.php b/tests/unit/price/ProgressivePriceTest.php
index 67e8e625..a7ee9250 100644
--- a/tests/unit/price/ProgressivePriceTest.php
+++ b/tests/unit/price/ProgressivePriceTest.php
@@ -215,4 +215,41 @@ private function progressivePriceProvider(): Generator
             ],
         ];
     }
+
+    /**
+     * @dataProvider progressivePriceProviderSmallUsage
+     */
+    public function testProgressivePriceSmallUsage(
+        array $inputThresholdsArray,
+        int $expectedAmount,
+        string $startPrice,
+        string $prepaid = '0'
+    ): void {
+        $price = $this->createProgressivePrice(
+            prepaid: $prepaid,
+            startPrice: $startPrice,
+            thresholdsArray: $inputThresholdsArray
+        );
+        $this->usage = Quantity::bps(6043);
+        $usage = $price->calculateUsage($this->usage);
+        $this->assertSame($this->usage->getQuantity(), $usage->getQuantity());
+
+        $amount = $price->calculateSum($this->usage);
+        $this->assertEquals($expectedAmount, $amount->getAmount());
+    }
+
+    private function progressivePriceProviderSmallUsage(): Generator
+    {
+        yield 'Simple case' => [
+            'thresholds' => [
+                ['price' => '10', 'currency' => 'EUR', 'quantity' => '0', 'unit' => 'gbps'],
+            ],
+            'money' => 0,
+            'price' => '1',
+            'prepaid' => '0',
+            'trace' => [
+                '6043bps * 0.00000001 = 0.00',
+            ],
+        ];
+    }
 }