useAwait

JavaScript (and super languages)

Summary

Rule available since: v1.4.0
Diagnostic Category: lint/suspicious/useAwait
This rule isn’t recommended, so you need to enable it.
This rule doesn’t have a fix.
The default severity of this rule is warning.
Sources:
- Same as require-await
- Same as @typescript-eslint/require-await

How to configure

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{
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  "linter": {
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    "rules": {
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      "suspicious": {
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        "useAwait": "error"
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      }
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    }
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  }
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}

Description

Ensure async functions utilize await.

This rule reports async functions that lack an await expression or another operation that requires async semantics. As async functions return a promise, the use of await is often necessary to capture the resolved value and handle the asynchronous operation appropriately. Without await, the function operates synchronously and might not leverage the advantages of async functions.

Examples

Invalid

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async function fetchData() {
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// Missing `await` for the promise returned by `fetch`
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  return fetch('/data');
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}

code-block.js:1:1 lint/suspicious/useAwait ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ This async function lacks an await expression.
  
  > 1 │ async function fetchData() {
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  > 2 │ // Missing `await` for the promise returned by `fetch`
  > 3 │   return fetch(‘/data’);
  > 4 │ }
      │ ^
    5 │ 
  
  ℹ Remove this async modifier, or add an await expression in the function.
  
  > 1 │ async function fetchData() {
      │ ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  > 2 │ // Missing `await` for the promise returned by `fetch`
  > 3 │   return fetch(‘/data’);
  > 4 │ }
      │ ^
    5 │ 
  
  ℹ Async functions without await expressions may not need to be declared async.

Valid

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async function fetchData() {
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  const response = await fetch('/data');
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  const data = await response.json();
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  return data;
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}
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// This rule does not warn about non-async functions
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function processData() {
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  return compute(data);
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}
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// Nor does it warn about empty `async` functions
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async function noop() { }
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// Async generators that use `yield*` with an async iterable
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async function* delegateToAsyncIterable() {
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  yield* otherAsyncIterable();
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}
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// `await using` awaits asynchronous resource disposal
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async function consumeResource() {
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  await using resource = acquire();
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  consume(resource);
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}