The Tor Browser: dom/browser-element/mochitest/browserElement_GetScreenshot.js@b8a032363ba2 (annotated)

dom/browser-element/mochitest/browserElement_GetScreenshot.js@b8a032363ba2 (annotated)

dom/browser-element/mochitest/browserElement_GetScreenshot.js

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* Any copyright is dedicated to the public domain.
    http://creativecommons.org/publicdomain/zero/1.0/ */
 // Test the getScreenshot property for mozbrowser
 "use strict";
 SimpleTest.waitForExplicitFinish();
 browserElementTestHelpers.setEnabledPref(true);
 browserElementTestHelpers.addPermission();
 function runTest() {
   var iframe1 = document.createElement('iframe');
   SpecialPowers.wrap(iframe1).mozbrowser = true;
   document.body.appendChild(iframe1);
   iframe1.src = 'data:text/html,<html>' +
     '<body style="background:green">hello</body></html>';
   var screenshotImageDatas = [];
   var numLoaded = 0;
   function screenshotTaken(screenshotImageData) {
     screenshotImageDatas.push(screenshotImageData);
     if (screenshotImageDatas.length === 1) {
       ok(true, 'Got initial non blank screenshot');
       var view = screenshotImageData.data;
       if (view[3] !== 255) {
         ok(false, 'The first pixel of initial screenshot is not opaque');
         SimpleTest.finish();
         return;
       }
       ok(true, 'Verified the first pixel of initial screenshot is opaque');
       iframe1.src = 'data:text/html,<html>' +
         '<body style="background:transparent">hello</body></html>';
       // Wait until screenshotImageData !== screenshotImageDatas[0].
       waitForScreenshot(function(screenshotImageData) {
         var view1 = screenshotImageData.data;
         var view2 = screenshotImageDatas[0].data;
         if (view1.length != view2.length) {
           return true;
         }
         for (var i = 0; i < view1.length; i++) {
           if (view1[i] != view2[i]) {
             return true;
           }
         }
         return false;
       }, 'image/png');
     }
     else if (screenshotImageDatas.length === 2) {
       ok(true, 'Got updated screenshot after source page changed');
       var view = screenshotImageData.data;
       if (view[3] !== 0) {
         // The case here will always fail when oop'd on Firefox Desktop,
         // but not on B2G Emulator
         // See https://bugzil.la/878003#c20
         var isB2G = (navigator.platform === '');
         info('navigator.platform: ' + navigator.platform);
         if (!isB2G && browserElementTestHelpers.getOOPByDefaultPref()) {
           todo(false, 'The first pixel of updated screenshot is not transparent');
         } else {
           ok(false, 'The first pixel of updated screenshot is not transparent');
         }
         SimpleTest.finish();
         return;
       }
       ok(true, 'Verified the first pixel of updated screenshot is transparent');
       SimpleTest.finish();
     }
   }
   // We continually take screenshots until we get one that we are
   // happy with.
   function waitForScreenshot(filter, mimeType) {
     function gotImage(e) {
       // |this| is the Image.
       URL.revokeObjectURL(this.src);
       if (e.type === 'error' || !this.width || !this.height) {
         tryAgain();
         return;
       }
       var canvas = document.createElement('canvas');
       canvas.width = canvas.height = 1000;
       var ctx = canvas.getContext('2d');
       ctx.drawImage(this, 0, 0);
       var imageData = ctx.getImageData(0, 0, 1000, 1000);
       if (filter(imageData)) {
         screenshotTaken(imageData);
         return;
       }
       tryAgain();
     }
     function tryAgain() {
       if (--attempts === 0) {
         ok(false, 'Timed out waiting for correct screenshot');
         SimpleTest.finish();
       } else {
         setTimeout(function() {
           iframe1.getScreenshot(1000, 1000, mimeType).onsuccess =
             getScreenshotImageData;
         }, 200);
       }
     }
     function getScreenshotImageData(e) {
       var blob = e.target.result;
       if (blob.type !== mimeType) {
         ok(false, 'MIME type of screenshot taken incorrect');
         SimpleTest.finish();
       }
       if (blob.size === 0) {
         tryAgain();
         return;
       }
       var img = new Image();
       img.src = URL.createObjectURL(blob);
       img.onload = img.onerror = gotImage;
     }
     var attempts = 10;
     iframe1.getScreenshot(1000, 1000, mimeType).onsuccess =
       getScreenshotImageData;
   }
   function iframeLoadedHandler() {
     numLoaded++;
     if (numLoaded === 2) {
       waitForScreenshot(function(screenshotImageData) {
         return true;
       }, 'image/jpeg');
     }
   }
   iframe1.addEventListener('mozbrowserloadend', iframeLoadedHandler);
 }
 addEventListener('testready', runTest);