Support `js/ts.hover.maximumLength` and `typescript.experimental.expandableHover`

[brc-dd]

Vue - Official extension or vue-tsc version

3.0.5

VSCode version

1.102.3

Vue version

3.5.18

TypeScript version

5.9.2

System Info

  System:
    OS: macOS 15.6
    CPU: (10) arm64 Apple M2 Pro
    Memory: 212.00 MB / 32.00 GB
    Shell: 5.9 - /bin/zsh
  Binaries:
    Node: 24.3.0 - ~/.local/state/fnm_multishells/30491_1754071350542/bin/node
    npm: 11.4.2 - ~/.local/state/fnm_multishells/30491_1754071350542/bin/npm
    pnpm: 10.13.1 - ~/.local/state/fnm_multishells/30491_1754071350542/bin/pnpm
    bun: 1.2.19 - /opt/homebrew/bin/bun
  Browsers:
    Safari: 18.6

package.json dependencies

{
  "type": "module",
  "dependencies": {
    "vue": "^3.5.18"
  },
  "devDependencies": {
    "typescript": "^5.9",
    "vue-tsc": "^3.0.5"
  }
}

Steps to reproduce

Create a file foo.ts with this:

type LessThan<N extends number, A extends any[] = []> = N extends A['length']
  ? A[number]
  : LessThan<N, [...A, A['length']]>

type NumericRange<F extends number, T extends number> = Exclude<
  T | LessThan<T>,
  LessThan<F>
>

type LongTuple = NumericRange<1, 150>

Add this to .vscode/settings.json:

{
  "js/ts.hover.maximumLength": 1000
}

What is expected?

Like it is with the extension disabled:

What is actually happening?

Link to minimal reproduction

No response

Any additional comments?

https://devblogs.microsoft.com/typescript/announcing-typescript-5-9/#configurable-maximum-hover-length

typescript.experimental.expandableHover too btw:

• with extension enabled:
  

• with extension disabled:
  

https://devblogs.microsoft.com/typescript/announcing-typescript-5-9/#expandable-hovers-(preview)

Edit: ah it's not a tuple, should've named it LongUnion 😅 I was copying the example from the TS PR but then thought it will get large to write all 150 values here, so picked up the snippet from SO.

[serkodev]

This issue can be resolved through Volar.js

I have submitted a pull request to resolve it.
volarjs/volar.js#285