ArgumentNullException in iOS LocalizedPrice(this SKProductDiscount product)

[mavaa]

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Bug Information

Version Number of Plugin: 1.2.5
Device Tested On: iPhone 6, iOS 11.3.1
Simulator Tested On: None
Version of VS: 15.6.7
Version of Xamarin: 4.9.0.753
Versions of other things you are using:

Steps to reproduce the Behavior

• Create an Auto renewing subscription with introductory price. Only localized to english, but prices set for all available contries
• Testing with a norwegian sandbox account, with english UI on the phone, not sure if this is relevant (prices show up as NOK, but all text and UI localization is in english).
• Run GetProductInfoAsync with the created product id

Expected Behavior

• Get a list of products

Actual Behavior

• I get an ArgumentNullException, because apparently SKProduct.IntroductoryPrice.PriceLocale is null, while SKProduct.PriceLocale is not. Happens in
  public static string LocalizedPrice(this SKProductDiscount product) src\Plugin.InAppBilling.iOS\InAppBillingImplementation.cs, line 548

I'm not sure if I've set something up wrong, or if this is a bug on the Xamarin or iOS side of things, but I've managed to do a workaround by changing the LocalizedPrice extension method to:
public static string LocalizedPrice(this SKProductDiscount product, NSLocale locale)

And the call on GetProductInfoAsync to:
LocalizedIntroductoryPrice = IsiOS112 ? (p.IntroductoryPrice?.LocalizedPrice(p.IntroductoryPrice?.PriceLocale ?? p.PriceLocale) ?? string.Empty) : string.Empty,

I can make a PR tomorrow is this is an acceptable fix, just wanted to check if anyone knows anything more about this issue than I can find out right now.

Code snippet

IInAppBilling billing = CrossInAppBilling.Current;

try
{
    bool connected = await billing.ConnectAsync();

    if (connected)
    {
        // Gets product id's from our server (only a single one in the test case)
        List<string> productIDs = this.GetProductIDs();

        // Exception happens here, when ToList triggers the Linq Select call in GetProductInfoAsync
        var subscriptions = (await billing.GetProductInfoAsync(ItemType.Subscription, productIDs.ToArray())).ToList();

        return subscriptions;
    }
}
catch (Exception ex)
{
    this.logger.LogError(ex);
}
finally
{
    await billing.DisconnectAsync();
}

return null;

Screenshots

Downloaded the project and stopped where the InAppBillingProduct(s) are created

[mavaa]

Thanks, I think I prefer my solution of falling back to SKProduct.PriceLocale if the other one is null as I can't see any scenario where they wouldn't be the same anyways. Do you want me to submit a PR for it, or do you prefer the version of returning string.empty?

[jamesmontemagno]

Already implemented and released in the pre-release :)