Protractor - what best way to check a string IS NOT empty in e2e testing

What is the best way to ensure a value is found (e.g not an empty string) using e2e testing, my example simply matches the text itself, I want to count the string length & ensure it isn't 0.

describe 'Device Details', ->
device = ionic.Platform.device()
details =
'deviceManufacturer': $('#deviceManufacturer'),
'deviceModel': $('#deviceModel')

it 'Device Manufacturer must not be empty', ->
  expect(details.deviceModel.getText()).toEqual '10'