Add getOptimisticInfo() method to track optimistic state per record

[KyleAMathews]

Summary

Implements collection.getOptimisticInfo(id) to provide rich metadata about optimistic state for a given record.

Returns:

• isOptimistic: boolean flag indicating if record has active mutations
• original: pre-mutation state (for updates)
• modified: current state including optimistic changes
• changes: delta of modifications (for updates)
• mutations: array of all active mutations affecting the record

Usage:

const info = collection.getOptimisticInfo(todoId)
if (info?.isOptimistic) {
  return <Badge>Saving...</Badge>
}

// Or for diff views:
if (info?.changes) {
  showDiff(info.original, info.modified, info.changes)
}

This provides everything needed for UI states like loading badges, diff views, and rollback UI while keeping records pure (no __optimistic field polluting user data).

Closes #20

Test plan

• ✅ Comprehensive test coverage (12 new tests)
• ✅ All existing tests pass (69 test files, 1289 tests)

[changeset-bot]

🦋 Changeset detected

Latest commit: 96e987e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 12 packages

Name	Type
@tanstack/db	Patch
@tanstack/angular-db	Patch
@tanstack/electric-db-collection	Patch
@tanstack/query-db-collection	Patch
@tanstack/react-db	Patch
@tanstack/rxdb-db-collection	Patch
@tanstack/solid-db	Patch
@tanstack/svelte-db	Patch
@tanstack/trailbase-db-collection	Patch
@tanstack/vue-db	Patch
todos	Patch
@tanstack/db-example-react-todo	Patch

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[pkg-pr-new]

More templates

• todos
• tanstack-start-db-projects-example
• @tanstack/db-example-react-todo
• @tanstack/db-example-solid-todo

@tanstack/angular-db

npm i https://pkg.pr.new/@tanstack/angular-db@660

@tanstack/db

npm i https://pkg.pr.new/@tanstack/db@660

@tanstack/db-ivm

npm i https://pkg.pr.new/@tanstack/db-ivm@660

@tanstack/electric-db-collection

npm i https://pkg.pr.new/@tanstack/electric-db-collection@660

@tanstack/query-db-collection

npm i https://pkg.pr.new/@tanstack/query-db-collection@660

@tanstack/react-db

npm i https://pkg.pr.new/@tanstack/react-db@660

@tanstack/rxdb-db-collection

npm i https://pkg.pr.new/@tanstack/rxdb-db-collection@660

@tanstack/solid-db

npm i https://pkg.pr.new/@tanstack/solid-db@660

@tanstack/svelte-db

npm i https://pkg.pr.new/@tanstack/svelte-db@660

@tanstack/trailbase-db-collection

npm i https://pkg.pr.new/@tanstack/trailbase-db-collection@660

@tanstack/vue-db

npm i https://pkg.pr.new/@tanstack/vue-db@660

commit: 96e987e

[github-actions]

Size Change: +464 B (+0.61%)

Total Size: 76.9 kB

Filename	Size	Change
./packages/db/dist/esm/collection/index.js	3.59 kB	+286 B (+8.65%)	🔍
./packages/db/dist/esm/collection/state.js	4 kB	+178 B (+4.65%)	🔍

ℹ️ View Unchanged

Filename	Size
./packages/db/dist/esm/collection/change-events.js	963 B
./packages/db/dist/esm/collection/changes.js	1.01 kB
./packages/db/dist/esm/collection/events.js	660 B
./packages/db/dist/esm/collection/indexes.js	1.16 kB
./packages/db/dist/esm/collection/lifecycle.js	1.82 kB
./packages/db/dist/esm/collection/mutations.js	2.52 kB
./packages/db/dist/esm/collection/subscription.js	1.83 kB
./packages/db/dist/esm/collection/sync.js	1.65 kB
./packages/db/dist/esm/deferred.js	230 B
./packages/db/dist/esm/errors.js	3.1 kB
./packages/db/dist/esm/index.js	1.58 kB
./packages/db/dist/esm/indexes/auto-index.js	828 B
./packages/db/dist/esm/indexes/base-index.js	835 B
./packages/db/dist/esm/indexes/btree-index.js	2 kB
./packages/db/dist/esm/indexes/lazy-index.js	1.21 kB
./packages/db/dist/esm/indexes/reverse-index.js	577 B
./packages/db/dist/esm/local-only.js	967 B
./packages/db/dist/esm/local-storage.js	2.33 kB
./packages/db/dist/esm/optimistic-action.js	294 B
./packages/db/dist/esm/proxy.js	3.86 kB
./packages/db/dist/esm/query/builder/functions.js	615 B
./packages/db/dist/esm/query/builder/index.js	4.04 kB
./packages/db/dist/esm/query/builder/ref-proxy.js	938 B
./packages/db/dist/esm/query/compiler/evaluators.js	1.55 kB
./packages/db/dist/esm/query/compiler/expressions.js	760 B
./packages/db/dist/esm/query/compiler/group-by.js	2.04 kB
./packages/db/dist/esm/query/compiler/index.js	2.04 kB
./packages/db/dist/esm/query/compiler/joins.js	2.52 kB
./packages/db/dist/esm/query/compiler/order-by.js	1.21 kB
./packages/db/dist/esm/query/compiler/select.js	1.28 kB
./packages/db/dist/esm/query/ir.js	785 B
./packages/db/dist/esm/query/live-query-collection.js	340 B
./packages/db/dist/esm/query/live/collection-config-builder.js	2.69 kB
./packages/db/dist/esm/query/live/collection-subscriber.js	1.92 kB
./packages/db/dist/esm/query/optimizer.js	3.08 kB
./packages/db/dist/esm/SortedMap.js	1.24 kB
./packages/db/dist/esm/transactions.js	3 kB
./packages/db/dist/esm/utils.js	1.01 kB
./packages/db/dist/esm/utils/browser-polyfills.js	365 B
./packages/db/dist/esm/utils/btree.js	6.01 kB
./packages/db/dist/esm/utils/comparison.js	754 B
./packages/db/dist/esm/utils/index-optimization.js	1.73 kB

_{compressed-size-action::db-package-size}

[github-actions]

Size Change: 0 B

Total Size: 1.47 kB

ℹ️ View Unchanged

Filename	Size
./packages/react-db/dist/esm/index.js	152 B
./packages/react-db/dist/esm/useLiveQuery.js	1.32 kB

_{compressed-size-action::react-db-package-size}

[KyleAMathews]

Closing this for now — @samwillis pointed out that using this in a component is problematic as the component doesn't necessarily re-render when a record goes from optimistic to synced so there needs to be a way to query a $status field on the record (or some similar design) so it's properly reactive.

This isn't a priority atm so we'll pick this up later.