TypeScript: Context.Provider value should not be assignable to undefined in the default case #1958
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Summary
Context providers should not accept
undefined
by default. Example of previously correct code we'd like to avoid:Assumption is that if you really wanted to allow providing
undefined
you would have written:This does not change the fact that
useContext
returnsundefined
if no default was provided:When combining Resources with Context, it is very easy to forget to test if a given resource is available before assigning it to the provider value.
How did you test this change?
I wrote an additional test to test the usage patterns.
This is type-level only change.