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• I have searched for related issues and found none that match my proposal.
• I have searched the current rule list and found no rules that match my proposal.
• I have read the FAQ and my problem is not listed.

My proposal is suitable for this project

• I believe my proposal would be useful to the broader TypeScript community (meaning it is not a niche proposal).

Link to the rule's documentation

https://typescript-eslint.io/rules/switch-exhaustiveness-check/

Description

This issue is there to discuss whether the requireDefaultForNonUnion option should be enabled by default.
This issue is not about whether the switch-exhaustiveness-check should be part of any preset or the option to be removed entirely.

Fail

declare const value: number;
switch (value) {
  case 0:
    return 0;
  case 1:
    return 1;
}

Pass

declare const value: number;
switch (value) {
  case 0:
    return 0;
  case 1:
    return 1;
  default:
    return -1;
}

Additional Info

Based on #7880 (comment)

• feat(eslint-plugin): [switch-exhaustiveness-check] add requireDefaultForNonUnion option #7880 (comment)

Partial previous discussion: #2959

• [switch-exhaustiveness-check] Require default case if discriminant type is not a union #2959