noUncheckedIndexedAccess w/ destructuring

[arcanis]

🔍 Search Terms

noUncheckedIndexedAccess, destructuring

✅ Viability Checklist

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• This feature would agree with the rest of our Design Goals: https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals

⭐ Suggestion

The ! qualifier should be allowed in destructuring patterns:

const [x!, y!, {z!}!] = someArrayValue;

📃 Motivating Example

This feature makes migrating a large codebase to noUncheckedIndexedAccess easier, as we no longer need to migrate all existing destructuring patterns in one go.

💻 Use Cases

We're working to enable noUncheckedIndexedAccess on a very large codebase (10k+ files). I wrote a codemod adding the ! qualifier to existing unchecked accesses, but while it's easy to do this on foo[expr] and foo.prop nodes, I didn't find a good solution for destructured accesses:

const [x, y, {z}] = someArrayValue;

The following doesn't parse, where it seems it should:

const [x!, y!, {z!}!] = someArrayValue;

[MartinJohns]

Partially a duplicate of #17390.

[typescript-bot]

This issue has been marked as "Duplicate" and has seen no recent activity. It has been automatically closed for house-keeping purposes.