I would like to capture the data from a webpage by using the querySelector and write a unit test to verify the data. But I don't know how to insert the Page to Jasmine for testing.For example:

In the main.js

function test()
{
  return document.querySelectorAll(`[id*="xxxxx"]`).length;
}

In the test.js

describe("test", function(){

        it("should be able to find the length", function() {
            expect(test()).toEqual(10);
        });
    });