fix(typescript-angular): enable "exactOptionalPropertyTypes" and ensure assignments align with type definition

[jase88]

fixes #20450

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[jase88]

@TiFu (2017/07) @taxpon (2017/07) @sebastianhaas (2017/07) @kenisteward (2017/07) @Vrolijkx (2017/09) @macjohnny (2018/01) @topce (2018/10) @akehir (2019/07) @petejohansonxo (2019/11) @amakhrov (2020/02) @davidgamero (2022/03) @mkusaka (2022/04) @joscha (2024/10)

When you have a moment, could you please take a look at my merge request and share your feedback? Thanks a lot!

[joscha]

Use ?? Or || ?

[jase88]

Maybe I misunderstand the suggestion to use the nullish coalescing operator, but if I use it I would have to specify a default value for withCredentials.

withCredentials is type of boolean and is optional, see here. With exactOptionalPropertyTypes an assignment of undefined wouldn't be allowed.

withCredentials: withCredentials ?? false seemed more like a breaking change

[jase88]

But I would be fine to go this route. I had a rough look at the Angular code and it seems that no distinction is made between undefined and false.

[joscha]

These are all guarded now, but beforehand they weren't, if the containing object was truthy all of them would have been set, no matter if truthy or not. Do we need to look into it in more detail on whether that behavior changes are fully backwards compatible?

[jase88]

That is absolutely correct. I have adapted it by explicitly checking for undefined. The only exceptions are encoder and apiKeys, as both can only be of data type truthy or undefined.

[macjohnny]

@joscha can you check whether this PR is ready? @jase88 can you fix the failing CI test?

[joscha]

I am not a user of the angular variant, but I am happy with the answers from @jase88. If there are truthy/undefined issues further down, we can adjust the code.