mirror of
https://github.com/Sevichecc/Urara-Blog.git
synced 2025-05-04 12:19:30 +08:00
124 lines
2.8 KiB
Text
124 lines
2.8 KiB
Text
---
|
|
description: 'Require Promise-like statements to be handled appropriately.'
|
|
---
|
|
|
|
> 🛑 This file is source code, not the primary documentation location! 🛑
|
|
>
|
|
> See **https://typescript-eslint.io/rules/no-floating-promises** for documentation.
|
|
|
|
A "floating" Promise is one that is created without any code set up to handle any errors it might throw.
|
|
|
|
Floating Promises can cause several issues, such as improperly sequenced operations, ignored Promise rejections, and more.
|
|
|
|
Valid ways of handling a Promise-valued statement include:
|
|
|
|
- `await`ing it
|
|
- `return`ing it
|
|
- Calling its `.then()` with two arguments
|
|
- Calling its `.catch()` with one argument
|
|
|
|
:::tip
|
|
`no-floating-promises` only detects unhandled Promise _statements_.
|
|
See [`no-misused-promises`](./no-misused-promises.md) for detecting code that provides Promises to _logical_ locations such as if statements.
|
|
:::
|
|
|
|
## Rule Details
|
|
|
|
Examples of code for this rule:
|
|
|
|
<!--tabs-->
|
|
|
|
### ❌ Incorrect
|
|
|
|
```ts
|
|
const promise = new Promise((resolve, reject) => resolve('value'));
|
|
promise;
|
|
|
|
async function returnsPromise() {
|
|
return 'value';
|
|
}
|
|
returnsPromise().then(() => {});
|
|
|
|
Promise.reject('value').catch();
|
|
|
|
Promise.reject('value').finally();
|
|
```
|
|
|
|
### ✅ Correct
|
|
|
|
```ts
|
|
const promise = new Promise((resolve, reject) => resolve('value'));
|
|
await promise;
|
|
|
|
async function returnsPromise() {
|
|
return 'value';
|
|
}
|
|
returnsPromise().then(
|
|
() => {},
|
|
() => {},
|
|
);
|
|
|
|
Promise.reject('value').catch(() => {});
|
|
|
|
Promise.reject('value').finally(() => {});
|
|
```
|
|
|
|
## Options
|
|
|
|
The rule accepts an options object with the following properties:
|
|
|
|
```ts
|
|
type Options = {
|
|
// if true, checking void expressions will be skipped
|
|
ignoreVoid?: boolean;
|
|
// if true, checking for async iife will be skipped
|
|
ignoreIIFE?: boolean;
|
|
};
|
|
|
|
const defaults = {
|
|
ignoreVoid: true,
|
|
ignoreIIFE: false,
|
|
};
|
|
```
|
|
|
|
### `ignoreVoid`
|
|
|
|
This allows you to stop the rule reporting promises consumed with void operator.
|
|
This can be a good way to explicitly mark a promise as intentionally not awaited.
|
|
|
|
Examples of **correct** code for this rule with `{ ignoreVoid: true }`:
|
|
|
|
```ts
|
|
async function returnsPromise() {
|
|
return 'value';
|
|
}
|
|
void returnsPromise();
|
|
|
|
void Promise.reject('value');
|
|
```
|
|
|
|
With this option set to `true`, and if you are using `no-void`, you should turn on the [`allowAsStatement`](https://eslint.org/docs/rules/no-void#allowasstatement) option.
|
|
|
|
### `ignoreIIFE`
|
|
|
|
This allows you to skip checking of async IIFEs (Immediately Invocated function Expressions).
|
|
|
|
Examples of **correct** code for this rule with `{ ignoreIIFE: true }`:
|
|
|
|
```ts
|
|
await(async function () {
|
|
await res(1);
|
|
})();
|
|
|
|
(async function () {
|
|
await res(1);
|
|
})();
|
|
```
|
|
|
|
## When Not To Use It
|
|
|
|
If you do not use Promise-like values in your codebase, or want to allow them to remain unhandled.
|
|
|
|
## Related To
|
|
|
|
- [`no-misused-promises`](./no-misused-promises.md)
|