Skip to main content

typescript/exhaustive-switch

Require a default branch in switch statements with multiple cases.

Targeted pattern scope​

This rule targets SwitchStatement nodes that:

  • have more than one case branch, and
  • have no default branch.

What this rule reports​

This rule reports non-trivial switch statements that have no default case.

Why this rule exists​

A required default branch reduces accidental non-exhaustive control flow.

❌ Incorrect​

switch (x) {
 case 1:
  break;
 case 2:
  break;
}

✅ Correct​

switch (x) {
 case 1:
  break;
 default:
  break;
}

Deprecated​

Behavior and migration notes​

This rule is deprecated in favor of @typescript-eslint/switch-exhaustiveness-check.

It reports only and does not provide an autofix.

Options​

This rule has no options.

Status​

Use the Deprecated section above for lifecycle details.

Additional examples​

switch (status) {
 case "ready":
  return 1;
}
// ✅ valid (single branch switch is outside this rule)

switch (status) {
 case "ready":
  return 1;
 case "done":
  return 2;
}
// ❌ reported: multiple branches and no default

ESLint flat config example​

import etcMisc from "eslint-plugin-etc-misc";

export default [
 {
  plugins: { "etc-misc": etcMisc },
  rules: {
   "etc-misc/typescript/exhaustive-switch": "error",
  },
 },
];

When not to use it​

Disable this rule if you intentionally omit default cases.

Package documentation​

Rule catalog ID: R084

Further reading​

Adoption resources​

  • Start at warning level in CI, then move to error after cleanup.
  • Use focused codemods/autofix batches per package or directory.