Improve return types for throwOnError

[Cryrivers]

What kind of change does this PR introduce?

This PR improves return types for throwOnError, which excludes null for failure responses in the return type. as throwOnError raises exceptions instead of providing a failure response.

What is the current behavior?

Currently throwOnError still types the return data as Data | null, whereas the null (failure response) case is impossible to happen.

What is the new behavior?

throwOnError just types the return data as Data (null is still kept if the data is nullable), if error happens, it throws an exception.

Additional context

This PR addresses supabase/supabase-js#554

TypeScript issue

TypeScript (4.8, 4.9) complains the circular references, however the types can be correctly inferred in Visual Studio Code.

src/PostgrestBuilder.ts:59:19 - error TS2577: Return type annotation circularly references itself.

59   throwOnError(): EnableThrowOnError<this> {

[Cryrivers]

i'm still figuring out how to type it correctly.

[TomasHubelbauer]

@Cryrivers Is there anything I can do to help get this over the line? I would also like to see this fix. Your last message says you're still figuring out the types. What is left to figure out to make the result unwrapping work after throwOnError?

[Cryrivers]

@Cryrivers Is there anything I can do to help get this over the line? I would also like to see this fix. Your last message says you're still figuring out the types. What is left to figure out to make the result unwrapping work after throwOnError?

right now the blocker is the TypeScript error: Return type annotation circularly references itself. I tried other workarounds with no luck. I'm not sure how to bypass the limitation of TypeScript at the moment. :(

[khill-fbmc]

I don't know much, but could this help at all with the types?

It claims to be super fast, recursive, and 1:1 with TypeScript

[mandarini]

Hi @Cryrivers ! Thanks for the contribution and your patience.

This repository is deprecated and has moved to the new Supabase JS monorepo. Since this PR has been inactive for over a year, I’m going to close it to keep the old repo tidy, before archiving.

If you believe this change is still needed, please open a new PR in the monorepo and include a link back to this thread for context:

• Monorepo: https://github.com/supabase/supabase-js
• Package location: packages/core//
• Migration guide: https://github.com/supabase/supabase-js/blob/master/docs/MIGRATION.md
• Contributing guide: https://github.com/supabase/supabase-js/blob/master/CONTRIBUTING.md

Note: This old repository will be archived on October 10, 2025. Thank you again for your effort and understanding!