# Suggest using `toBeNull()` (`prefer-to-be-null`)

## Deprecated

This rule has been deprecated in favor of [`prefer-to-be`](prefer-to-be.md).

In order to have a better failure message, `toBeNull()` should be used upon
asserting expectations on null value.

## Rule details

This rule triggers a warning if `toBe()`, `toEqual()` or `toStrictEqual()` is
used to assert a null value.

```js
expect(null).toBe(null);
```

This rule is enabled by default.

### Default configuration

The following patterns are considered warnings:

```js
expect(null).toBe(null);

expect(null).toEqual(null);

expect(null).toStrictEqual(null);
```

The following pattern is not warning:

```js
expect(null).toBeNull();
```