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sablier/node_modules/hook-std/readme.md

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# hook-std
> Hook and modify stdout and stderr
## Install
```sh
npm install hook-std
```
## Usage
```js
import assert from 'node:assert';
import {hookStdout} from 'hook-std';
const promise = hookStdout(output => {
promise.unhook();
assert.strictEqual(output.trim(), 'unicorn');
});
console.log('unicorn');
await promise;
```
You can also unhook using the second `transform` method parameter:
```js
import assert from 'node:assert';
import {hookStdout} from 'hook-std';
const promise = hookStdout((output, unhook) => {
unhook();
assert.strictEqual(output.trim(), 'unicorn');
});
console.log('unicorn');
await promise;
```
## API
### hookStd(options?, transform)
Hook streams in [`streams` option](#streams), or stdout and stderr if none are specified.
Returns a `Promise` with a `unhook()` method which, when called, unhooks both stdout and stderr and resolves the `Promise` with an empty result.
### hookStdout(options?, transform)
Hook stdout.
Returns a `Promise` with a `unhook()` method which, when called, unhooks stdout and resolves the `Promise` with an empty result.
### hookStderr(options?, transform)
Hook stderr.
Returns a `Promise` with a `unhook()` method which, when called, unhooks stderr and resolves the `Promise` with an empty result.
#### options
Type: `object`
##### silent
Type: `boolean`\
Default: `true`
Suppress stdout/stderr output.
##### once
Type: `boolean`\
Default: `false`
Automatically unhook after the first call.
##### streams
Type: `stream.Writable[]`\
Default: `[process.stdout, process.stderr]`
The [writable streams](https://nodejs.org/api/stream.html#stream_writable_streams) to hook. This can be useful for libraries allowing users to configure a writable stream to write to.
#### transform
Type: `Function`
Receives stdout/stderr as the first argument and the unhook method as the second argument. Return a string to modify it. Optionally, when in silent mode, you may return a `boolean` to influence the return value of `.write(…)`.