# id-denylist

> Disallow the identifier names you list

Names like `data`, `tmp` or `cb` don't say much about what they hold. This rule reports the names you list when they name a variable, parameter, function, class, import, object key or class member, or a property you assign to.

Without a list, the rule reports nothing.

{/* 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]
"id-denylist" = "error" # or "warn"
```

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

## Examples

```toml bunfig.toml
[lint.rules]
id-denylist = ["error", "data", "callback"]
```

Reported:

{/* bad {"options": ["data", "callback"], "count": 4} */}
```js
const data = loadUser(id);

function save(user, callback) {}

const response = { data: 1 };
response.data = 2;
```

Not reported:

{/* good {"options": ["data", "callback"]} */}
```js
const user = loadUser(id);

function save(user, onSaved) {}
```

A variable is reported where it's declared and again where it's used, except where it's called or passed as an argument. This example gets two reports, on lines 1 and 3:

{/* bad {"options": ["data"], "count": 2} */}
```js
function render(data) {
  log(data);
  return data.title;
}
```

Reading a property is allowed, because the object may come from code you don't control. So is an import or a destructured property that you rename:

{/* good {"options": ["data", "callback"]} */}
```js
import { data as users } from "./api";

const { data: orders } = await fetchOrders();

console.log(response.data, users, orders);
```

Private names are compared without the `#`:

{/* bad {"options": ["data"]} */}
```js
class Store {
  #data = new Map();
}
```

## Options

Each option is a name to disallow. Names are compared exactly, so `"data"` doesn't match `userData`.