I'd like to use the mock $window object only for my isSecure directive. I'd like to use the real $window in the isSecure.spec.js test file. Note the errors when running the tests due to the mock $window being used in the test code as well.

isSecure.js

angular.module( 'validators.isSecure', [] )

.directive( 'isSecure', function( $window ) {
    'use strict';

    var SECURE_URL_REGEX = /^https|^\//;
    var HTTP_PROTOCOL = 'http:';
    var ERROR_KEY = 'isSecure';

    return {
        require : 'ngModel',
        link : function( scope, el, attrs, ngModel ) {
            ngModel.$parsers.unshift( function( viewValue ) {
                var isSecure = SECURE_URL_REGEX.test( viewValue ) || $window.location.protocol === HTTP_PROTOCOL;
                ngModel.$setValidity( ERROR_KEY, isSecure );
                return viewValue;
            } );
        }
    };
} );

isSecure.spec.js

describe( 'isSecure validator', function() {
    var $window;
    var $compile;
    var $rootScope;
    var htmlString;
    var httpsUrl;
    var httpUrl;
    var relativeUrl;
    var protocolRelativeUrl;


    beforeEach( module( 'validators.isSecure' ) );

    beforeEach( function() {
        $window = {
            location : {
                protocol : 'https:'
            }
        };
        module( function( $provide ) {
            $provide.value('$window', $window);
        } );
    } );

    beforeEach( inject( function( _$compile_, _$rootScope_ ) {
        $compile = _$compile_;
        $rootScope = _$rootScope_;
        htmlString = '<form name="form"><input name="url" ng-model="url" is-secure></form>';
        $compile( htmlString )( $rootScope );
        httpsUrl = 'https://example.com/photo.jpg';
        httpUrl = 'http://example.com/photo.jpg';
        relativeUrl = '/photo.jpg';
        protocolRelativeUrl = '//example.com/photo.jpg';

    } ) );

    it( 'should treat an undefined ng-model as valid', function() {
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( true );
    } );

    it( 'should treat an empty string as valid', function() {
        $rootScope.form.url.$setViewValue( '' );
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( true );
    } );

    it( 'should treat a https url as valid', function() {
        $rootScope.form.url.$setViewValue( httpsUrl );
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( true );
    } );

    it( 'should treat a relative url as valid', function() {
        $rootScope.form.url.$setViewValue( relativeUrl );
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( true );
    } );

    it( 'should treat a protocol-relative url as valid', function() {
        $rootScope.form.url.$setViewValue( protocolRelativeUrl );
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( true );
    } );

    it( 'should treat a http url as invalid', function() {
        $rootScope.form.url.$setViewValue( httpUrl );
        $rootScope.$digest();
        expect( $rootScope.form.url.$valid ).toBe( false );
    } );

} );

test run output

PhantomJS 1.9.8 (Mac OS X) isSecure validator should treat a https url as valid FAILED
    TypeError: 'undefined' is not a function (evaluating 'document.createElement('div')')
        at /Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:14220
        at textInputType (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:17035)
        at /Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:17403
        at nodeLinkFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:6705)
        at compositeLinkFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:6098)
        at nodeLinkFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:6698)
        at compositeLinkFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:6098)
        at publicLinkFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:5994)
        at /Users/jtherrell/src/myapp/myapp-ui/src/common/validators/isSecure/isSecure.spec.js:29
        at invoke (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular/angular.js:3966)
        at workFn (/Users/jtherrell/src/myapp/myapp-ui/vendor/angular-mocks/angular-mocks.js:2159)
    Expected false to be true.