signal-desktop/test/views/attachment_view.js

describe('AttachmentView', function() {

  it('should display an error for an unsupported type', function() {
    var attachment = { contentType: 'html/text' };
    var view = new Whisper.AttachmentView({model: attachment}).render();
    assert.match(view.$el.text(), /Sorry, your attachment has a type, html, that is not currently supported./);
  });

});