The regular expression should not use the g flag.

Chai uses re.exec when it tests a regular expression re. This regular expression matches '000' and its lastIndex is set to 3 (because the g flag is set). The next test calls re.exec('110'). The match starts from the new lastIndex position and it fails.

There is something weird indeed with the tests, if you only leave that one in the sample tests, your code passes it. But, your code is not ok, and it returns true for any combination of 0 and 1 with 3 digits.

Test failing even though it is a match when I console.log the test using

multipleOf3Regex.test('110')

My solution is

const multipleOf3Regex = /^[0-1]{3}$/g

No, they are not identical:

                                v
expected 'Jacob and Alex like ths' 
to equal 'Jacob and Alex like this'
                                ^

The kata doesn't seem to work for me. 4 tests comes back similar to the statement below:

expected 'Jacob and Alex like ths' to equal 'Jacob and Alex like this'

Are they not identical?!