Count Component

count.js

/**
 * Interface for a count, affected by remote addition or subtraction
 * event should send data with 'property' property, set to eg: -1 to lower by one
 */
define(function(require) {
    'use strict';

    var defineComponent = require('flight/lib/component');

    function Count() {
        this.defaultAttrs({
            'event': null
        });

        this.after('initialize', function() {
            this.on(document, this.attr.event, this.update.bind(this));
        });

        this.update = function(event, data) {
            this.$node.text(
                parseInt(this.$node.text(), 10) + data.modifier
            );
        }
    }

    return defineComponent(Count);
});

count.spec.js

describeComponent('component_ui/count', function () {

    beforeEach(function () {
        setupComponent('<span>8</span>', {'event': 'uiChangeCount'});
    });

    describe('receiving event', function() {
        it('applies a positive modifier', function() {
            $(document).trigger('uiChangeCount', {'modifier': 3});
            expect(this.component.$node).toHaveText('11');
        });

        it('applies a negative modifier', function() {
            $(document).trigger('uiChangeCount', {'modifier': -1});
            expect(this.component.$node).toHaveText('7');
        });
    });
});