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useAwait (since v1.4.0)

Diagnostic Category: lint/suspicious/useAwait

Sources:

Ensure async functions utilize await.

This rule reports async functions that lack an await expression. 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

Section titled Examples

Invalid

Section titled Invalid
async function fetchData() {
// Missing `await` for the promise returned by `fetch`
  return fetch('/data');
}
suspicious/useAwait.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

Section titled Valid
async function fetchData() {
  const response = await fetch('/data');
  const data = await response.json();
  return data;
}


// This rule does not warn about non-async functions
function processData() {
  return compute(data);
}


// Nor does it warn about empty `async` functions
async function noop() { }
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