asyncPromiseExecutors

Reports using async functions as Promise executor functions.

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

The Promise executor function is called synchronously by the Promise constructor. If an async function is used as a Promise executor, thrown errors will not be caught by the Promise and will instead result in unhandled rejections. Additionally, if a Promise executor function is using await, there’s probably no need to use the new Promise constructor - you can return the awaited value or use the Promise directly.

const 
const result: Promise<unknown>
result = new 
var Promise: PromiseConstructor
new <unknown>(executor: (resolve: (value: unknown) => void, reject: (reason?: any) => void) => void) => Promise<unknown>
Creates a new Promise.
@param ― executor A callback used to initialize the promise. This callback is passed two arguments:
a resolve callback used to resolve the promise with a value or the result of another promise,
and a reject callback used to reject the promise with a provided reason or error.
Promise(async (
resolve: (value: unknown) => void
resolve, 
reject: (reason?: any) => void
reject) => {
  const 
const data: Response
data = await 
function fetch(input: string | URL | Request, init?: RequestInit): Promise<Response> (+1 overload)
MDN Reference
fetch("/api");
  
resolve: (value: unknown) => void
resolve(
const data: Response
data);
});

new 
var Promise: PromiseConstructor
new <unknown>(executor: (resolve: (value: unknown) => void, reject: (reason?: any) => void) => void) => Promise<unknown>
Creates a new Promise.
@param ― executor A callback used to initialize the promise. This callback is passed two arguments:
a resolve callback used to resolve the promise with a value or the result of another promise,
and a reject callback used to reject the promise with a provided reason or error.
Promise(async function (
resolve: (value: unknown) => void
resolve, 
reject: (reason?: any) => void
reject) {
  try {
    
resolve: (value: unknown) => void
resolve(await 
const asyncOperation: any
asyncOperation());
  } catch (
function (local var) error: unknown
error) {
    
reject: (reason?: any) => void
reject(
function (local var) error: unknown
error);
  }
});

const 
const result: Promise<unknown>
result = new 
var Promise: PromiseConstructor
new <unknown>(executor: (resolve: (value: unknown) => void, reject: (reason?: any) => void) => void) => Promise<unknown>
Creates a new Promise.
@param ― executor A callback used to initialize the promise. This callback is passed two arguments:
a resolve callback used to resolve the promise with a value or the result of another promise,
and a reject callback used to reject the promise with a provided reason or error.
Promise((
resolve: (value: unknown) => void
resolve, 
reject: (reason?: any) => void
reject) => {
  
function fetch(input: string | URL | Request, init?: RequestInit): Promise<Response> (+1 overload)
MDN Reference
fetch("/api")
    .
Promise<Response>.then<void, never>(onfulfilled?: ((value: Response) => void | PromiseLike<void>) | null | undefined, onrejected?: ((reason: any) => PromiseLike<never>) | null | undefined): Promise<void>
Attaches callbacks for the resolution and/or rejection of the Promise.
@param ― onfulfilled The callback to execute when the Promise is resolved.
@param ― onrejected The callback to execute when the Promise is rejected.
@returns ― A Promise for the completion of which ever callback is executed.
then((
data: Response
data) => 
resolve: (value: unknown) => void
resolve(
data: Response
data))
    .
Promise<void>.catch<void>(onrejected?: ((reason: any) => void | PromiseLike<void>) | null | undefined): Promise<void>
Attaches a callback for only the rejection of the Promise.
@param ― onrejected The callback to execute when the Promise is rejected.
@returns ― A Promise for the completion of the callback.
catch((
error: any
error) => 
reject: (reason?: any) => void
reject(
error: any
error));
});

// Or even better, use the async function directly:
const 
const result: () => Promise<Response>
result = async () => {
  return await 
function fetch(input: string | URL | Request, init?: RequestInit): Promise<Response> (+1 overload)
MDN Reference
fetch("/api");
};

Options

This rule is not configurable.

When Not To Use It

If you have very old, complex logic that is difficult to refactor, you might consider disabling this rule on a per-case basis.

Equivalents in Other Linters

Biome: noAsyncPromiseExecutor
Deno: no-async-promise-executor
ESLint: no-async-promise-executor
Oxlint: eslint/no-async-promise-executor

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asyncPromiseExecutors

Examples

Options

When Not To Use It

Further Reading

Equivalents in Other Linters