asyncUnnecessaryPromiseWrappers

Reports unnecessary Promise.resolve() or Promise.reject() in async contexts.

✅ This rule is included in the ts logical and logicalStrict presets.

Wrapping a return value in Promise.resolve() in an async function or a promise callback is unnecessary because return values are already wrapped in a Promise. Similarly, returning an error wrapped in Promise.reject() is equivalent to throwing the error. This applies to yield expressions in async generators as well.

async function 
function getValue(): Promise<number>
getValue() {
  return 
var Promise: PromiseConstructor
Represents the completion of an asynchronous operation
Promise.
PromiseConstructor.resolve<number>(value: number): Promise<number> (+2 overloads)
Creates a new resolved promise for the provided value.
@param ― value A promise.
@returns ― A promise whose internal state matches the provided promise.
resolve(42);
}

async function 
function failWithError(): Promise<never>
failWithError() {
  return 
var Promise: PromiseConstructor
Represents the completion of an asynchronous operation
Promise.
PromiseConstructor.reject<never>(reason?: any): Promise<never>
Creates a new rejected promise for the provided reason.
@param ― reason The reason the promise was rejected.
@returns ― A new rejected Promise.
reject(new 
var Error: ErrorConstructor
new (message?: string) => Error
Error("failed"));
}


const promise: any
promise.
any
then(() => 
var Promise: PromiseConstructor
Represents the completion of an asynchronous operation
Promise.
PromiseConstructor.resolve<number>(value: number): Promise<number> (+2 overloads)
Creates a new resolved promise for the provided value.
@param ― value A promise.
@returns ― A promise whose internal state matches the provided promise.
resolve(42));


const promise: any
promise.
any
catch(() => 
var Promise: PromiseConstructor
Represents the completion of an asynchronous operation
Promise.
PromiseConstructor.reject<never>(reason?: any): Promise<never>
Creates a new rejected promise for the provided reason.
@param ― reason The reason the promise was rejected.
@returns ― A new rejected Promise.
reject(new 
var Error: ErrorConstructor
new (message?: string) => Error
Error("error")));

async function 
function getValue(): Promise<number>
getValue() {
  return 42;
}

async function 
function failWithError(): Promise<void>
failWithError() {
  throw new 
var Error: ErrorConstructor
new (message?: string) => Error
Error("failed");
}


const promise: any
promise.
any
then(() => 42);


const promise: any
promise.
any
catch(() => {
  throw new 
var Error: ErrorConstructor
new (message?: string) => Error
Error("error");
});

function 
function regularFunction(): Promise<number>
regularFunction() {
  return 
var Promise: PromiseConstructor
Represents the completion of an asynchronous operation
Promise.
PromiseConstructor.resolve<number>(value: number): Promise<number> (+2 overloads)
Creates a new resolved promise for the provided value.
@param ― value A promise.
@returns ― A promise whose internal state matches the provided promise.
resolve(42);
}

Options

This rule is not configurable.

When Not To Use It

If you have a codebase that intentionally uses Promise.resolve() and Promise.reject() for consistency across async and non-async functions, you may want to disable this rule.

Equivalents in Other Linters

ESLint: unicorn/no-useless-promise-resolve-reject
Oxlint: unicorn/no-useless-promise-resolve-reject

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asyncUnnecessaryPromiseWrappers

Examples

Options

When Not To Use It

Further Reading

Equivalents in Other Linters