fix: improve autocomplete for session keys

[ascorbic]

Changes

Use the | (string & {}) trick to ensure that key autocomplete always works

Testing

Docs

[changeset-bot]

🦋 Changeset detected

Latest commit: 4b604f3

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[florian-lefebvre]

Gotta love this trick!

[codspeed-hq]

CodSpeed Performance Report

Merging #13622 will not alter performance

_{Comparing key-autocomp (4b604f3) with main (406501a)}

Summary

✅ 6 untouched benchmarks

[ematipico]

Out of curiosity, what does this trick do?

[ascorbic]

@ematipico It lets you type something to accept any string, but also get autocomplete from a string union. If type something as SomeStringUnion | string then it resolves to just string, so you get no autocomplete, but due to a TypeScript quirk, typing it as SomeStringUnion | (string & {}) means it accepts any string but still gives autocomplete for the union values. This is so useful the TS team has decided to not fix the "bug".