[DO_NOT_MERGE] sync effect (V2) development and testing

[dmaskasky]

Summary

Uploading syncEffect v2 work in progress to finish development. The end goal is all tests pass.

The full implementation is provided towards this goal.

Not for merge

Current State

✅ All tests passing

 ✓  jotai  tests/syncEffect/syncEffect.test.tsx (32 tests) 126ms
   ✓ should run the effect on vanilla store
   ✓ should run the effect on mount and cleanup on unmount and whenever countAtom changes
   ✓ should not cause infinite loops when effect updates the watched atom
   ✓ should not cause infinite loops when effect updates the watched atom asynchronous
   ✓ should allow synchronous recursion with set.recurse for first run
   ✓ should allow synchronous recursion with set.recurse
   ✓ should allow multiple synchronous recursion with set.recurse
   ✓ should batch updates during synchronous recursion with set.recurse
   ✓ should allow asynchronous recursion with task delay with set.recurse
   ✓ should allow asynchronous recursion with microtask delay with set.recurse
   ✓ should work with both set.recurse and set
   ✓ should disallow synchronous set.recurse in cleanup
   ✓ should return value from set.recurse
   ✓ should conditionally run the effect and cleanup when effectAtom is unmounted
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is +0 and incrementCountBy is +0
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is +0 and incrementCountBy is 1
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is +0 and incrementCountBy is 2
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 1 and incrementCountBy is +0
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 1 and incrementCountBy is 1
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 1 and incrementCountBy is 2
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 2 and incrementCountBy is +0
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 2 and incrementCountBy is 1
   ✓ synchronous updates to the same atom > when effectIncrementCountBy is 2 and incrementCountBy is 2
   ✓ should batch effect setStates
   ✓ should batch synchronous updates as a single transaction
   ✓ should run the effect once even if the effect is mounted multiple times
   ✓ should abort the previous promise
   ✓ should not infinite loop with nested atomEffects
   ✓ should not rerun with get.peek
   ✓ should throw on set when an error is thrown in effect
   ✓ should throw on set when an error is thrown in cleanup
   ✓ should not suspend the component

 Test Files  1 passed (1)
      Tests  32 passed (32)
   Start at  02:51:18
   Duration  247ms

Check List

• pnpm run fix:format for formatting code and docs

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Name	Status	Preview	Comments	Updated (UTC)
jotai	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jan 21, 2025 7:35pm

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commit: 9147721

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Latest commit: 9147721
Last updated: Jan 21, 2025 7:34pm (UTC)

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