The reason for wrapping here was quite simple - without wrapping the test itself is failing to finish, looks like this error is "counted" like run time error (or smth. like that) by Jasmine runner.
```
..................................................................x....
PromiseService:: is throwing exception when supplied number of arguments is incorrect: failed
  CAPIError: Wrong number of arguments provided for promise-based function. in file:///C:/Workspace/EZ/ez-js-rest-client/src/services/PromiseService.js (line 25) (1)
275 specs in 1.024s.
>> 1 failures
Warning: Task "jasmine:test" failed. Use --force to continue.
```

But I guess the proposed matcher approach will help, since it will catch the error on the fly.