consistent-return

Require return statements to either always or never specify values.

💭

This rule requires type information to run.

This rule extends the base eslint/consistent-return rule. This version adds support for functions that return void or Promise<void>.

warning

If possible, it is recommended to use tsconfig's noImplicitReturns option rather than this rule. noImplicitReturns is powered by TS's type information and control-flow analysis so it has better coverage than this rule.

❌ Incorrect

function foo(): undefined {}
function bar(flag: boolean): undefined {
  if (flag) return foo();
  return;
}

async function baz(flag: boolean): Promise<undefined> {
  if (flag) return;
  return foo();
}

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✅ Correct

function foo(): void {}
function bar(flag: boolean): void {
  if (flag) return foo();
  return;
}

async function baz(flag: boolean): Promise<void | number> {
  if (flag) return 42;
  return;
}

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Options

See eslint/consistent-return's options.

How to Use

Flat Config

eslint.config.mjs

export default tseslint.config({
  rules: {
    // Note: you must disable the base rule as it can report incorrect errors
    "consistent-return": "off",
    "@typescript-eslint/consistent-return": "error"
  }
});

Legacy Config

.eslintrc.cjs

module.exports = {
  "rules": {
    // Note: you must disable the base rule as it can report incorrect errors
    "consistent-return": "off",
    "@typescript-eslint/consistent-return": "error"
  }
};

Try this rule in the playground ↗

When Not To Use It

Type checked lint rules are more powerful than traditional lint rules, but also require configuring type checked linting.

See Troubleshooting > Linting with Type Information > Performance if you experience performance degradations after enabling type checked rules.

Resources

• Rule source
• Test source

^{Taken with ❤️ from ESLint core.}