# unicorn/no-new-buffer

> Require `Buffer.from()` or `Buffer.alloc()` instead of the deprecated `new Buffer()`

`new Buffer(value)` allocates that many bytes if `value` is a number, and copies `value` if it's a string or an array. If user input turns out to be a number where you expected a string, the call allocates memory instead of copying text. Node.js deprecated the constructor for this reason. `Buffer.alloc()` and `Buffer.from()` each do one thing.

`--fix-suggestions` picks `Buffer.alloc()` when the first argument is a number literal, and `Buffer.from()` when it's a string, a template literal, or an array literal. It leaves other calls alone.

{/* Generated by src/codegen/lint-rule-docs.ts. Do not edit this section. */}

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"unicorn/no-new-buffer" = "error" # or "warn"
```

{/* End of the generated section. */}

## Examples

Reported:

{/* bad {"count": 2} */}
```js
const header = new Buffer(16);
const name = new Buffer("Ada", "utf8");
```

Not reported:

{/* good */}
```js
const header = Buffer.alloc(16);
const name = Buffer.from("Ada", "utf8");
```