Parse 'customerSheetClientSecret' for Android and iOS

[tjclawson-stripe]

Summary

Add logic to parse customerSessionClientSecret

Motivation

Support Customer Session for React Native
MOBILESDK-2432
MOBILESDK-2431

Testing

• I tested this manually
• I added automated tests

Documentation

Select one:

• I have added relevant documentation for my changes.
• This PR does not result in any developer-facing changes.

[charliecruzan-stripe]

looking good, one nit about error handling and also could you add the type declaration for the new field to https://github.com/stripe/stripe-react-native/blob/master/src/types/PaymentSheet.ts#L13-L70 ?

[charliecruzan-stripe]

do we want to add error handling if they provide both customerSessionClientSecret and customerEphemeralKeySecret?

[tjclawson-stripe]

Updated 👍

[tjclawson-stripe]

looking good, one nit about error handling and also could you add the type declaration for the new field to https://github.com/stripe/stripe-react-native/blob/master/src/types/PaymentSheet.ts#L13-L70 ?

Added the types to PaymentSheet.ts, but it doesn't seem to actually throw an error if both values are set. It's throwing an exception if both are set so it's fine, but is there a way for typescript to actually throw an error?

[charliecruzan-stripe]

Added the types to PaymentSheet.ts, but it doesn't seem to actually throw an error if both values are set. It's throwing an exception if both are set so it's fine, but is there a way for typescript to actually throw an error?

No TS won't throw an error (depending on your typescript config, compilation may fail) it'll just complain in the IDE, but that's good enough since we're also throwing an error in the native layer anyways