Create unified error enums or types

[vegaro]

https://stackoverflow.com/questions/58410482/exposing-all-revenuecat-purchaseserrorcode-codes-in-flutter?sem=2

Expose error codes as enums or equivalent in Dart so they don't have to be hard-coded.

The proposed solution would be to add something like this

enum PurchasesErrorCode {
  UnknownError,
  PurchaseCancelledError,
  StoreProblemError,
  PurchaseNotAllowedError,
  PurchaseInvalidError,
  ProductNotAvailableForPurchaseError,
  ProductAlreadyPurchasedError,
  ReceiptAlreadyInUseError,
  InvalidReceiptError,
  MissingReceiptFileError,
  NetworkError,
  InvalidCredentialsError,
  UnexpectedBackendResponseError,
  ReceiptInUseByOtherSubscriberError,
  InvalidAppUserIdError,
  OperationAlreadyInProgressError,
  UnknownBackendError,
  InsufficientPermissionsError
}

try {
} on PlatformException catch (e) {
  PurchasesErrorCode errorCode = PurchasesErrorCode.values[int.parse(e.code)];
  switch (errorCode) {
    case PurchasesErrorCode.UnknownError:
    case PurchasesErrorCode.PurchaseCancelledError:
    case PurchasesErrorCode.StoreProblemError:
    // Add rest of cases
  }
}

[IchordeDionysos]

Would be useful!

[vegaro]

Fixed on https://github.com/RevenueCat/purchases-flutter/releases/tag/1.0.0

You can do this now:

       try {
          PurchaserInfo purchaserInfo = await Purchases.purchasePackage(package);
        } on PlatformException catch (e) {
          var errorCode = PurchasesErrorHelper.getErrorCode(e);
          if (errorCode == PurchasesErrorCode.purchaseCancelledError) {
            print("User cancelled");
          } else if (errorCode == PurchasesErrorCode.purchaseNotAllowedError) {
            print("User not allowed to purchase");
          }
        }