securityos/node_modules/eslint-plugin-jest/docs/rules/prefer-to-contain.md

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# Suggest using `toContain()` (`prefer-to-contain`)
💼 This rule is enabled in the 🎨 `style`
[config](https://github.com/jest-community/eslint-plugin-jest/blob/main/README.md#shareable-configurations).
🔧 This rule is automatically fixable by the
[`--fix` CLI option](https://eslint.org/docs/latest/user-guide/command-line-interface#--fix).
<!-- end auto-generated rule header -->
In order to have a better failure message, `toContain()` should be used upon
asserting expectations on an array containing an object.
## Rule details
This rule triggers a warning if `toBe()`, `toEqual()` or `toStrictEqual()` is
used to assert object inclusion in an array
```js
expect(a.includes(b)).toBe(true);
```
```js
expect(a.includes(b)).not.toBe(true);
```
```js
expect(a.includes(b)).toBe(false);
```
The following patterns are considered warnings:
```js
expect(a.includes(b)).toBe(true);
expect(a.includes(b)).not.toBe(true);
expect(a.includes(b)).toBe(false);
expect(a.includes(b)).toEqual(true);
expect(a.includes(b)).toStrictEqual(true);
```
The following patterns are not considered warnings:
```js
expect(a).toContain(b);
expect(a).not.toContain(b);
```