Bump typescript from 5.9.3 to 6.0.2

[dependabot]

Bumps typescript from 5.9.3 to 6.0.2.

Release notes

Sourced from typescript's releases.

TypeScript 6.0

For release notes, check out the release announcement blog post.

• fixed issues query for TypeScript 6.0.0 (Beta).
• fixed issues query for TypeScript 6.0.1 (RC).
• fixed issues query for TypeScript 6.0.2 (Stable).

Downloads are available on:

• npm

TypeScript 6.0 Beta

For release notes, check out the release announcement.

• fixed issues query for Typescript 6.0.0 (Beta).

Downloads are available on:

• npm

Commits

• 607a22a Bump version to 6.0.2 and LKG
• 9e72ab7 🤖 Pick PR #63239 (Fix missing lib files in reused pro...) into release-6.0 (#...
• 35ff23d 🤖 Pick PR #63163 (Port anyFunctionType subtype fix an...) into release-6.0 (#...
• e175b69 Bump version to 6.0.1-rc and LKG
• af4caac Update LKG
• 8efd7e8 Merge remote-tracking branch 'origin/main' into release-6.0
• 206ed1a Deprecate assert in import() (#63172)
• e688ac8 Update dependencies (#63156)
• 29b300d Bump the github-actions group across 1 directory with 2 updates (#63205)
• 0c2c7a3 DOM update (#63183)
• Additional commits viewable in compare view

[raineorshine]

@copilot Suggest a migration path to upgrade to Typescript v6

[Copilot]

@copilot Suggest a migration path to upgrade to Typescript v6

Here's a migration path for upgrading to TypeScript v6. The good news is this project is already in great shape — strict: true is already set, no namespaces are used, and no import ... assert syntax exists. Running tsc --noEmit against v6.0.2 shows only 2 deprecation warnings (treated as errors), with zero actual type errors.

---

Phase 1: Fix deprecation errors (required now)

Only two issues block compilation:

1. downlevelIteration is deprecated — Since target is "es2018" which natively supports iterators, downlevelIteration is unnecessary. Remove it from tsconfig.json.

2. moduleResolution: "node" (aka node10) is deprecated — Replace with "moduleResolution": "bundler" which is the correct setting for Vite-based projects. This is the recommended resolution strategy for apps using a bundler and matches how Vite actually resolves modules.

After these two changes, tsc --noEmit passes cleanly with v6.0.2.

Phase 2: Recommended cleanup (optional but advised)

3. Bump target from "es2018" to "es2022" — Aligns with the "lib": ["dom", "es2022"] already set. Since Vite handles transpilation, the target here mainly affects type-checking and emit helpers.

4. Update sub-package configs:

   • server/package.json still pins TypeScript at ^4.9.4 — consider upgrading it too, or at minimum ensure it's compatible.
   • Several scripts/*/tsconfig.json files extend the main tsconfig and set "module": "commonjs" — these are fine for now, but CommonJS may see stricter treatment in TS 7.0.

5. Update @typescript-eslint packages — The current ^8.54.0 should work with TS 6, but verify by running yarn lint.

Phase 3: Prepare for TypeScript 7.0 (Go rewrite)

6. TS 6.0 is the last JS-based compiler. For a smooth transition to v7:
   • Avoid moduleResolution: "node10" and downlevelIteration (will stop working entirely).
   • Keep module/target settings explicit — defaults change significantly in v7.
   • Monitor @typescript-eslint and vite-plugin-checker for v7 compatibility.

---

TL;DR: Remove downlevelIteration and change moduleResolution to "bundler" in tsconfig.json. That's all that's needed to make this build pass on TS 6.0.2.

[raineorshine]

@copilot Open a new PR and begin the migration.

[Copilot]

@raineorshine I've opened a new pull request, #4030, to work on those changes. Once the pull request is ready, I'll request review from you.

[dependabot]

Superseded by #4170.