Payment flow cancellation exceptions from flutter_stripe are not caught by try-catch blocks

[WaliHassanKhan]

Describe the bug
When using the flutter_stripe package, if the user cancels the payment flow, a StripeException is thrown with FailureCode.Canceled (clicking outside the payment box), but this exception does not get caught by surrounding try-catch blocks in Dart async methods. Instead it crashes the app.

cancelling await Stripe.instance.presentPaymentSheet() would crash the app
if you don't use await. It wont crash the app.

To Reproduce

try {
await Stripe.instance.confirmPayment(
paymentIntentClientSecret,
PaymentMethodParams.card(),
);
// Payment confirmed
} on StripeException catch (e) {
// This should catch the cancellation, but does not
print('Stripe Error: ${e.error.localizedMessage}');
} catch (e) {
// Other errors
print('Other Error: $e');
}
Result: The cancellation exception is not caught by any of the catch handlers above.

flutter_stripe: ^11.5.0

Expected behavior
The debugger would go to the await Stripe.instance.presentPaymentSheet();
line and show you the exception.

_$StripeExceptionImpl (StripeException(error: LocalizedErrorMessage(code: FailureCode.Canceled, localizedMessage: The payment flow has been canceled, message: The payment flow has been canceled, ...)))

However, it would not go to the catch block.

Smartphone / tablet

• Iphone pro 16
• pixel 8

Additional context:
This breaks the standard Dart exception handling flow and makes handling Stripe errors much harder. Please advise if there's a workaround or if this needs to be fixed at the plugin level.

[remonh87]

I think there must be something wrong in your current application because we do exactly what you state and we get the StripeException nicely in our try catch block. See:

flutter_stripe/example/lib/screens/payment_sheet/payment_sheet_screen.dart

Line 148 in b0d2c6d

Future<void> confirmPayment() async {

I think somewhere you miss concurrency awaiting because we use standard dart exception throwing.

[WaliHassanKhan]

Apologies for the misunderstanding. The code block I posted earlier was summarized by AI and I didn't proofread it.

I'm actually having trouble with the presentPaymentSheet.

try { await Stripe.instance.presentPaymentSheet(); } on StripeException catch (e) { if (!context.mounted) return; ScaffoldMessenger.of(context).showSnackBar( SnackbarUtils.errorSnackBar( 'Payment failed: ${e.error.localizedMessage}', ), ); return; } catch (e) { if (!context.mounted) return; ScaffoldMessenger.of(context).showSnackBar( SnackbarUtils.errorSnackBar( 'Payment failed: ${e.toString()}', ), ); return; }
If you click outside the payment sheet, it does not reach the catch block.
The following code without the await doesn't work either. But it doesn't crash the app.

Stripe.instance.presentPaymentSheet().then((value) { if (!context.mounted) return; // Check if the widget is still mounted onSuccess({'shouldUpdateMetadata': true}); // Payment successful ScaffoldMessenger.of(context).showSnackBar( SnackbarUtils.successSnackBar( 'Payment successful', ), ); // Optionally, navigate to another screen or perform other actions }).onError((error, stackTrace) { if (!context.mounted) return; // Handle payment error ScaffoldMessenger.of(context).showSnackBar( SnackbarUtils.errorSnackBar( 'Payment failed', ), ); });

[WaliHassanKhan]

this only happens during the debug mode.
The app would stop and go straight to this exception.
If i run it without the debug mode. It won't stop the flow.