EqualError returns a function that checks for a specific error text.

ErrorAs returns a function that checks that error can be converted to a specific type.

ErrorContains returns a function that checks that error message contains a specific text.

ErrorIs returns a function that checks that error is equal to a specific error.

ErrorRegexp returns a function that checks that error message matches a specific regexp.

ErrorTagIs returns a function that checks that error has a specific tag.

NoError returns a function that checks that no error happened.

Check is a function that checks for an error or absence of it.