Phase4: Stripe

src/lib/stripe.ts

@@ -182,16 +182,27 @@ export async function createCheckoutSessionForInvoice(params: {
   // Stripe Checkout supports a limited set of locales; map our
   // four to Stripe's codes and fall back to 'auto' if anything
   // outside the set ever appears.
-  const stripeLocale: Stripe.Checkout.SessionCreateParams.Locale =
+  //
+  // We deliberately don't annotate this with
+  // `Stripe.Checkout.SessionCreateParams.Locale` — stripe-node v22
+  // ships with a known type-export regression
+  // (stripe/stripe-node#2662) where params types under namespaced
+  // resources aren't re-exported from the resource barrel. The
+  // `as const` literal narrowing gives the variable the union type
+  // `"de" | "fr" | "it" | "en" | "auto"`, which `sessions.create`
+  // accepts at the call site via its own inline parameter typing.
+  // When the SDK fixes the re-export, we can put the annotation
+  // back without touching the call site.
+  const stripeLocale =
     invoice.locale === "de"
-      ? "de"
+      ? ("de" as const)
       : invoice.locale === "fr"
-      ? "fr"
+      ? ("fr" as const)
       : invoice.locale === "it"
-      ? "it"
+      ? ("it" as const)
       : invoice.locale === "en"
-      ? "en"
-      : "auto";
+      ? ("en" as const)
+      : ("auto" as const);
 
   const successUrl = `${baseUrl}/billing/${encodeURIComponent(invoice.invoiceNumber)}?paid=1&session_id={CHECKOUT_SESSION_ID}`;
   const cancelUrl = `${baseUrl}/billing/${encodeURIComponent(invoice.invoiceNumber)}?cancelled=1`;