How To Write A Jasmine Test For Printer Function

I am trying to write a Jasmine test for the following print function: printContent( contentName: string ) { this._console.Information( `${this.codeName}.printContent: ${conte

Solution 1:

You must make sure, window.open() returns a fully featured object since the printContent method under test uses properties and functions of windowPrint. Such an object is typically created with createSpyObj.

var doc = jasmine.createSpyObj('document', ['write', 'close']);
var windowPrint = jasmine.createSpyObj('windowPrint', ['focus', 'print', 'close']);
windowPrint.document = doc; 
spyOn(window, 'open').and.returnValue(windowPrint);

Your amended unit test would then look as follows:

it( 'printContent should open a window ...', () => {

  // givenvar doc = jasmine.createSpyObj('document', ['write', 'close']);
  var windowPrint = jasmine.createSpyObj('windowPrint', ['focus', 'print', 'close']);
  windowPrint.document = doc;
  spyOn(window, 'open').and.returnValue(windowPrint);

  // when
  sut.printContent('printContent');

  // thenexpect(window.open).toHaveBeenCalledWith('', '', 'left=0,top=0,width=925,height=1400,toolbar=0,scrollbars=0,status=0');
  expect(doc.write).toHaveBeenCalled(); 
  expect(doc.close).toHaveBeenCalled(); 
  expect(windowPrint.focus).toHaveBeenCalled(); 
  expect(windowPrint.print).toHaveBeenCalled(); 
  expect(windowPrint.close).toHaveBeenCalled(); 
});