Testing the interaction with html and JavaScript using Jasmine is wrong?

JavaScript code has some html interactions like this example:

function retornaListaDeItens(argument) {
  return document.getElementsByClassName(argument);
}

I use the return of this function to perform operations in JavaScript, performing unit tests using Jasmine I came across the following scenario of doubts:

The test framework uses Jasmine's own SpecRunner.html file and has no contact with the html where it has the list of items to return in this example, making it difficult for unit tests.

The structure looks something like this:

app
  lib
  --bootstrap
  --jasmine
  src
  --css
  --js
    --teste.js
  test
  --testeSpec.js
  index.html

The test idea looks like this:

  it("retorno de lista de itens não deve ser vazio", function() {
    var item = "item";
    var list = retornaListaDeItens(item);
    console.log(list.length);
    expect(list).not.toBeLessThan(0);
  });