How to check multiple checkboxes in Protractor

I've seen how to check one checkbox via this link: How to validate when a checkbox is checked in AngularJS e2e tests?

However I would like to know how to do this to check if all checkboxes that I have on my view are going to be checked.

At the moment the code below only checks if one checkbox has been selected:

    .clickElementById('user-' + data.userIndex)
    .expect(
        element('input[ng-model="user.checked"]')
        .attr('checked')
    ).toBeTruthy()

Which is what I want however when I go onto my next test of selecting all checkboxes via a button I would like to loop through all of the checkboxes to test if they have been selected. Apologies to repeat myself.

Ta