third_party/WebKit/LayoutTests/fast/repaint/resources/text-based-repaint.js

   1 // Asynchronous tests should manually call finishRepaintTest at the appropriate
   2 // time.
   3 window.testIsAsync = false;
   4 window.outputRepaintRects = true;
   5 window.generateMinimumRepaint = false; // See comments about 'Minimum repaint' below.
   6
   7 // All repaint tests are asynchronous.
   8 if (window.testRunner)
   9     testRunner.waitUntilDone();
  10
  11 function runRepaintTest()
  12 {
  13     if (!window.testRunner || !window.internals) {
  14         setTimeout(repaintTest, 500);
  15         return;
  16     }
  17
  18     // TODO(enne): this is a workaround for multiple svg onload events.
  19     // See: http://crbug.com/372946
  20     if (window.hasRunRepaintTest)
  21         return;
  22     window.hasRunRepaintTest = true;
  23
  24     if (window.enablePixelTesting)
  25         testRunner.dumpAsTextWithPixelResults();
  26     else
  27         testRunner.dumpAsText();
  28
  29     function continueRepaintTest()
  30     {
  31         window.internals.startTrackingRepaints(document);
  32         repaintTest();
  33         if (!window.testIsAsync)
  34             finishRepaintTest();
  35     }
  36
  37     if (window.generateMinimumRepaint) {
  38         testRunner.capturePixelsAsyncThen(function(width, height, snapshot) {
  39             window.widthBeforeRepaint = width;
  40             window.heightBeforeRepaint = height;
  41             window.snapshotBeforeRepaint = snapshot;
  42             continueRepaintTest();
  43         });
  44     } else {
  45         testRunner.layoutAndPaintAsyncThen(continueRepaintTest);
  46     };
  47 }
  48
  49 function runRepaintAndPixelTest()
  50 {
  51     window.enablePixelTesting = true;
  52     runRepaintTest();
  53 }
  54
  55 function forceStyleRecalc()
  56 {
  57     if (document.body)
  58         document.body.offsetTop;
  59     else if (document.documentElement)
  60         document.documentElement.offsetTop;
  61 }
  62
  63 function finishRepaintTest()
  64 {
  65     if (!window.testRunner || !window.internals)
  66         return;
  67
  68     // Force a style recalc.
  69     forceStyleRecalc();
  70
  71     var repaintRects = window.internals.layerTreeAsText(document, window.internals.LAYER_TREE_INCLUDES_REPAINT_RECTS | window.internals.LAYER_TREE_INCLUDES_PAINT_INVALIDATION_OBJECTS);
  72
  73     internals.stopTrackingRepaints(document);
  74
  75     function repaintTestDone()
  76     {
  77         // Play nice with JS tests which may want to print out assert results.
  78         if (window.isJsTest)
  79             window.outputRepaintRects = false;
  80
  81         if (window.outputRepaintRects)
  82             testRunner.setCustomTextOutput(repaintRects);
  83
  84         if (window.afterTest)
  85             window.afterTest();
  86
  87         // Play nice with async JS tests which want to notifyDone themselves.
  88         if (!window.jsTestIsAsync)
  89             testRunner.notifyDone();
  90     }
  91
  92     if (window.generateMinimumRepaint) {
  93         internals.forceFullRepaint(document);
  94         testRunner.capturePixelsAsyncThen(function(width, height, snapshot) {
  95             if (window.outputRepaintRects) {
  96                 var minimumRepaint = computeMinimumRepaint(width, height, snapshot);
  97                 if (minimumRepaint.length)
  98                     repaintRects += '\nMinimum repaint:\n' + JSON.stringify(minimumRepaint, null, 2);
  99             }
 100             repaintTestDone();
 101         });
 102     } else {
 103         repaintTestDone();
 104     }
 105 }
 106
 107 // Minimum repaint
 108 //
 109 // Definitions
 110 // - minimum-repaint = region(diff(snapshot-before-repaintTest,
 111 //                                 snapshot-after-repaintTest-and-full-repaint))
 112 //   It includes all pixels that should be changed after repaintTest.
 113 // - actual-repaint = repaint rects recorded during repaintTest() and
 114 //   forceStyleRecalc().
 115 // - potential-under-repaint = subtract(minimum-repaint, actual-repaint)
 116 //   Potential-under-repaint will be shown in layout test overlay in black if
 117 //   any minimum-repaint region is not covered by actual-repaint.
 118 //
 119 // Potential-under-repaints don't always mean bug:
 120 // - Some know visualization issues (crbug.com/381221) may cause false
 121 //   under-repaint;
 122 // - Screen updates caused by composited layer re-compositing may not need
 123 //   repaint.
 124 //
 125 // How to use
 126 // 1. Set window.generateMinimumRepaint to true in some repaint test or change
 127 //    this script to force window.generateMinimumRepaint to true.
 128 // 2. Run layout tests. Repaint tests will result text diffs, which is because
 129 //    of the minimum repaint output in the actual results and doesn't mean the
 130 //    tests failed.
 131 // 3. In layout test result page, click 'overlay' link or expand the test to
 132 //    see the 'overlay' pane.
 133 // 4. Click 'Highlight under-repaint' button. You'll see black region if there
 134 //    is any under-repaint.
 135 //
 136 // Known issues
 137 //    crbug.com/381221
 138
 139 function computeMinimumRepaint(width, height, snapshot)
 140 {
 141     var result = [];
 142     if (width > widthBeforeRepaint) {
 143         result.push([widthBeforeRepaint, 0, width - widthBeforeRepaint, Math.max(height, heightBeforeRepaint)]);
 144         width = widthBeforeRepaint;
 145     }
 146     if (height > heightBeforeRepaint) {
 147         result.push([0, heightBeforeRepaint, width, height - heightBeforeRepaint]);
 148         height = heightBeforeRepaint;
 149     }
 150
 151     var dataBefore = new Uint32Array(snapshotBeforeRepaint);
 152     var dataAfter = new Uint32Array(snapshot);
 153     var rectsMayContinue = [];
 154     var index = 0;
 155     for (var y = 0; y < height; ++y) {
 156         var x = 0;
 157         var rectsMayContinueIndex = 0;
 158         var nextRectsMayContinue = [];
 159         while (true) {
 160             while (x < width && dataBefore[index] == dataAfter[index]) {
 161                 ++x;
 162                 ++index;
 163             }
 164             xBegin = x;
 165             while (x < width && dataBefore[index] != dataAfter[index]) {
 166                 ++x;
 167                 ++index;
 168             }
 169             xEnd = x;
 170
 171             var xWidth = xEnd - xBegin;
 172             if (!xWidth)
 173                 break;
 174
 175             var rectMayContinue = rectsMayContinue[rectsMayContinueIndex];
 176             while (rectMayContinue && rectMayContinue[0] < xBegin)
 177                 rectMayContinue = rectsMayContinue[++rectsMayContinueIndex];
 178
 179             if (rectMayContinue && rectMayContinue[0] == xBegin && rectMayContinue[2] == xWidth) {
 180                 ++rectMayContinue[3];
 181                 nextRectsMayContinue.push(rectMayContinue);
 182             } else {
 183                 var newRect = [xBegin, y, xWidth, 1];
 184                 nextRectsMayContinue.push(newRect);
 185                 result.push(newRect);
 186             }
 187         }
 188         rectsMayContinue = nextRectsMayContinue;
 189     }
 190     return result;
 191 }