improve error message for templates with currency-only amount

1 files changed, 19 insertions, 8 deletions

diff --git a/packages/taler-wallet-core/src/operations/pay-merchant.ts b/packages/taler-wallet-core/src/operations/pay-merchant.ts
index 63bef3add..1039ac95e 100644
--- a/packages/taler-wallet-core/src/operations/pay-merchant.ts
+++ b/packages/taler-wallet-core/src/operations/pay-merchant.ts
@@ -640,7 +640,8 @@ async function processDownloadProposal(
 
   if (proposal.purchaseStatus != PurchaseStatus.PendingDownloadingProposal) {
     logger.error(
-      `unexpected state ${proposal.purchaseStatus}/${PurchaseStatus[proposal.purchaseStatus]
+      `unexpected state ${proposal.purchaseStatus}/${
+        PurchaseStatus[proposal.purchaseStatus]
       } for ${ctx.transactionId} in processDownloadProposal`,
     );
     return TaskRunResult.finished();
@@ -899,7 +900,8 @@ async function createOrReusePurchase(
     oldProposal.claimToken === claimToken
   ) {
     logger.info(
-      `Found old proposal (status=${PurchaseStatus[oldProposal.purchaseStatus]
+      `Found old proposal (status=${
+        PurchaseStatus[oldProposal.purchaseStatus]
       }) for order ${orderId} at ${merchantBaseUrl}`,
     );
     if (oldProposal.purchaseStatus === PurchaseStatus.DialogShared) {
@@ -1567,12 +1569,21 @@ export async function preparePayForTemplate(
     throw Error("invalid taler-template URI");
   }
   logger.trace(`parsed URI: ${j2s(parsedUri)}`);
-  if (
-    parsedUri.templateParams.amount !== undefined &&
-    typeof parsedUri.templateParams.amount === "string"
-  ) {
-    templateDetails.amount = (req.templateParams?.amount ??
-      parsedUri.templateParams.amount) as AmountString | undefined;
+
+  const amountFromUri = parsedUri.templateParams.amount;
+  if (amountFromUri != null) {
+    const templateParamsAmount = req.templateParams?.amount;
+    if (templateParamsAmount != null) {
+      templateDetails.amount = templateParamsAmount as AmountString;
+    } else {
+      if (Amounts.isCurrency(amountFromUri)) {
+        throw Error(
+          "Amount from template URI only has a currency without value. The value must be provided in the templateParams.",
+        );
+      } else {
+        templateDetails.amount = amountFromUri as AmountString;
+      }
+    }
   }
   if (
     parsedUri.templateParams.summary !== undefined &&