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