Product.products(for:) always returns empty results

Number:rdar://FB9217524 Date Originated:June 28, 2021, 3:48PM
Status:Open Resolved:
Product:StoreKit Product Version:
Classification:Incorrect/Unexpected Behavior Reproducible:
This used to work correctly right after the WWDC announcement of SK2, but it stopped working at one point. 
FWIW it stopped working before the method got renamed (it used to be request(with:)). 

I have tried the method using the SKDemo app (updating the methods to their new names after beta 2)

I’ve also tried this with my own testing app. In both cases, I tried with StoreKit Config files, and in my own app I also tried without the config file. 

However, SKProductsRequest still works correctly for the same app, for the same product identifiers. 
This is currently blocking me from even testing out StoreKit 2, since this method is the basis for most of the API. 

Expected behavior: 
products(for:) would return products for existing product ids. 

products(for:) always returns an empty set. 

I spotted this in the logs: 

[StoreKit:0df2] Failed to decode Product:
typeMismatch(for: [StoreKit.Product.Key.attributes, StoreKit.Product.Key.description, StoreKit.Product.Key.standard], expected: Swift.String)


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