hidpi.js

   1 /**
   2  * @fileoverview Tests for window.devicePixelRatio > 1.
   3  *
   4  * @author danvdk@gmail.com (Dan Vanderkam)
   5  */
   6
   7 import Dygraph from '../../src/dygraph';
   8
   9 describe("hidpi", function() {
  10
  11 cleanupAfterEach();
  12
  13 var savePixelRatio;
  14 beforeEach(function() {
  15   savePixelRatio = window.devicePixelRatio;
  16   window.devicePixelRatio = 2;
  17 });
  18
  19 afterEach(function() {
  20   window.devicePixelRatio = savePixelRatio;
  21 });
  22
  23 it('testDoesntCreateScrollbars', function() {
  24   var sw = document.body.scrollWidth;
  25   var cw = document.body.clientWidth;
  26
  27   var graph = document.getElementById("graph");
  28   graph.style.width = "70%";  // more than half.
  29   graph.style.height = "200px";
  30
  31   var opts = {};
  32   var data = "X,Y\n" +
  33       "0,-1\n" +
  34       "1,0\n" +
  35       "2,1\n" +
  36       "3,0\n"
  37   ;
  38
  39   var g = new Dygraph(graph, data, opts);
  40
  41   // Adding the graph shouldn't cause the width of the page to change.
  42   // (essentially, we're checking that we don't end up with a scrollbar)
  43   // See http://stackoverflow.com/a/2146905/388951
  44   assert.equal(cw, document.body.clientWidth);
  45   assert.equal(sw, document.body.scrollWidth);
  46 });
  47
  48
  49 });