prefer-to-be-null.md 612 Bytes

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

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.

expect(null).toBe(null);

This rule is enabled by default.

Default configuration

The following patterns are considered warnings:

expect(null).toBe(null);

expect(null).toEqual(null);

expect(null).toStrictEqual(null);

The following pattern is not warning:

expect(null).toBeNull();