From dd82a56ec52facdee6b1318e94ed68d34c306e40 Mon Sep 17 00:00:00 2001
From: "Carlos R. L. Rodrigues"
 <37986729+carlos-r-l-rodrigues@users.noreply.github.com>
Date: Mon, 19 Aug 2024 14:19:49 -0300
Subject: [PATCH] fix(payment-stripe): fix smallest unit calculation (#8663)

---
 .../payment-stripe/src/core/stripe-base.ts     |  5 +++--
 .../src/utils/__tests__/get-smallest-unit.ts   | 18 ++++++++++++++++++
 .../src/utils/get-smallest-unit.ts             |  2 +-
 3 files changed, 22 insertions(+), 3 deletions(-)
 create mode 100644 packages/modules/providers/payment-stripe/src/utils/__tests__/get-smallest-unit.ts

diff --git a/packages/modules/providers/payment-stripe/src/core/stripe-base.ts b/packages/modules/providers/payment-stripe/src/core/stripe-base.ts
index a8d0dc5576..e0ee2e3f76 100644
--- a/packages/modules/providers/payment-stripe/src/core/stripe-base.ts
+++ b/packages/modules/providers/payment-stripe/src/core/stripe-base.ts
@@ -18,6 +18,7 @@ import {
   PaymentSessionStatus,
   isDefined,
   isPaymentProviderError,
+  isPresent,
 } from "@medusajs/utils"
 import {
   ErrorCodes,
@@ -281,7 +282,7 @@ abstract class StripeBase extends AbstractPaymentProvider<StripeOptions> {
 
       return result
     } else {
-      if (amount && data.amount === amountNumeric) {
+      if (isPresent(amount) && data.amount === amountNumeric) {
         return { data }
       }
 
@@ -302,7 +303,7 @@ abstract class StripeBase extends AbstractPaymentProvider<StripeOptions> {
     try {
       // Prevent from updating the amount from here as it should go through
       // the updatePayment method to perform the correct logic
-      if (data.amount) {
+      if (isPresent(data.amount)) {
         throw new MedusaError(
           MedusaError.Types.INVALID_DATA,
           "Cannot update amount, use updatePayment instead"
diff --git a/packages/modules/providers/payment-stripe/src/utils/__tests__/get-smallest-unit.ts b/packages/modules/providers/payment-stripe/src/utils/__tests__/get-smallest-unit.ts
new file mode 100644
index 0000000000..824755e003
--- /dev/null
+++ b/packages/modules/providers/payment-stripe/src/utils/__tests__/get-smallest-unit.ts
@@ -0,0 +1,18 @@
+import { getSmallestUnit } from "../get-smallest-unit"
+
+describe("getSmallestUnit", () => {
+  it("should convert an amount to the format required by Stripe based on currency", () => {
+    // 0 decimals
+    expect(getSmallestUnit(50098, "JPY")).toBe(50098)
+
+    // 3 decimals
+    expect(getSmallestUnit(5.124, "KWD")).toBe(5130)
+
+    // 2 decimals
+    expect(getSmallestUnit(100.54, "USD")).toBe(10054)
+    expect(getSmallestUnit(5.126, "KWD")).toBe(5130)
+    expect(getSmallestUnit(0.54, "USD")).toBe(54)
+    expect(getSmallestUnit(0.054, "USD")).toBe(5)
+    expect(getSmallestUnit(0.005104, "USD")).toBe(0)
+  })
+})
diff --git a/packages/modules/providers/payment-stripe/src/utils/get-smallest-unit.ts b/packages/modules/providers/payment-stripe/src/utils/get-smallest-unit.ts
index de4e36788a..89de8068b4 100644
--- a/packages/modules/providers/payment-stripe/src/utils/get-smallest-unit.ts
+++ b/packages/modules/providers/payment-stripe/src/utils/get-smallest-unit.ts
@@ -56,7 +56,7 @@ export function getSmallestUnit(
     numeric = Math.ceil(numeric / 10) * 10
   }
 
-  return numeric
+  return parseInt(numeric.toString().split(".").shift()!, 10)
 }
 
 /**