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Tokenising failure on parenthesis-wrapped object literal's type assertion operators `as keyof typeof`

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
typescript
Domain
tooling

Research direction

Start by inspecting the repository's TypeScript TextMate grammar files and reproduce the supplied examples in the relevant editor syntax highlighter. Compare the highlighting of as keyof typeof in the parenthesis-wrapped object literal with the other examples; done means those operators receive keyword scopes rather than variable.parameter.ts or the TSX equivalent.

Written by the indexing model from the issue text.

Description

JavaScript and TypeScript Nightly version: 5.3.0-dev.20231015

Code

This is the minimal and possible code for compare and constrast.
The example might not cover all posibilities that leads to this issue.

type A = { a: "", b: "" }
const a = { a: "", b: "" }

const c = ({
    key: a.a, label: a.b[a.a as keyof typeof a.b]
})

const d = (
    {
        key: a.a, label: a.b[a.a as keyof typeof a.b]
    })

const e =
    { key: a.a, label: a.b[a.a as keyof typeof a.b] }

const f =
{
    key: a.a, label: a.b[a.a as keyof typeof a.b]
}

When the object literal is going to be written like d, the inner operator as keyof typeof is tokenised as variable.parameter.ts or (tsx), but not keyword.*.

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Dominant language
TypeScript
Stars
471
Forks
149
No merged PRs in 30d

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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