--- description: 'Disallow returning a value with type `any` from a function.' --- > 🛑 This file is source code, not the primary documentation location! 🛑 > > See **https://typescript-eslint.io/rules/no-unsafe-return** for documentation. Despite your best intentions, the `any` type can sometimes leak into your codebase. Returned `any` typed values are not checked at all by TypeScript, so it creates a potential safety hole, and source of bugs in your codebase. ## Rule Details This rule disallows returning `any` or `any[]` from a function. This rule also compares the return type to the function's declared/inferred return type to ensure you don't return an unsafe `any` in a generic position to a receiver that's expecting a specific type. For example, it will error if you return `Set` from a function declared as returning `Set`. Examples of code for this rule: ### ❌ Incorrect ```ts function foo1() { return 1 as any; } function foo2() { return Object.create(null); } const foo3 = () => { return 1 as any; }; const foo4 = () => Object.create(null); function foo5() { return [] as any[]; } function foo6() { return [] as Array; } function foo7() { return [] as readonly any[]; } function foo8() { return [] as Readonly; } const foo9 = () => { return [] as any[]; }; const foo10 = () => [] as any[]; const foo11 = (): string[] => [1, 2, 3] as any[]; // generic position examples function assignability1(): Set { return new Set([1]); } type TAssign = () => Set; const assignability2: TAssign = () => new Set([true]); ``` ### ✅ Correct ```ts function foo1() { return 1; } function foo2() { return Object.create(null) as Record; } const foo3 = () => []; const foo4 = () => ['a']; function assignability1(): Set { return new Set(['foo']); } type TAssign = () => Set; const assignability2: TAssign = () => new Set(['foo']); ``` There are cases where the rule allows to return `any` to `unknown`. Examples of `any` to `unknown` return that are allowed. ```ts function foo1(): unknown { return JSON.parse(singleObjString); // Return type for JSON.parse is any. } function foo2(): unknown[] { return [] as any[]; } ``` ## Options ```jsonc // .eslintrc.json { "rules": { "@typescript-eslint/no-unsafe-return": "error" } } ``` This rule is not configurable. ## Related To - [`no-explicit-any`](./no-explicit-any.md)