How to unit test angularjs form?

Question

I have been learning AngularJS and things have been going pretty smoothly regarding unit testing, but I've reached a bit of a tricky spot.

Suppose I have a simple form, for example:

<form name="form">
    <input type="text" name="number" ng-pattern="/^d+$/">
</form>

If I was testing something like a controller, I know that I would write it something like this (using Jasmine + Karma):

beforeEach(module('some.module'));

beforeEach(inject(/* services */) {
    /* inject necessary services */
});

it('should be invalid when given bad input', function () {
    form.number = 'Not a number';
    expect(form.number.$valid).toBeFalsy();
    expect(form.$valid).toBeFalsy();
});

But I don't know which services I need to inject, and I haven't had any luck finding documentation on unit testing in either the forms guide or the ng-form documentation.

How does one unit test a form in Angular?

Answer 1

I'm not convinced this is the best way to unit test something like this but with some help from this answer on testing custom angular directives and some experimentation, I figured out a way to unit test the form.

After installing karma-ng-html2js-preprocessor and configuring it, I managed to get a working unit test like this:

var scope, form;

beforeEach(function() {
  module('my-module');
  module('templates');
});

beforeEach(inject($rootScope, $controller, $templateCache, $compile) {
    scope = $rootScope.$new()

    ctrl = $controller('MyController'), {
        "$scope": scope
    }

    templateHtml = $templateCache.get('path/to/my/template.html')
    formElem = angular.element("<div>" + templateHtml + "</div>")
    $compile(formElem)(scope)
    form = scope.form

    scope.$apply()
}

it('should not allow an invalid `width`', function() {
  expect(form.$valid).toBeTruthy();
  form.number.$setViewValue('BANANA');
  expect(form.number.$valid).toBeFalsy()
});