gecko/content/canvas/test/webgl/log-more-info-about-test-failures.patch

# HG changeset patch
# Parent 1910ae60536dce7272cb0478089bf40806666de8
diff --git a/content/canvas/test/webgl/conformance/glsl/misc/glsl-function-nodes.html b/content/canvas/test/webgl/conformance/glsl/misc/glsl-function-nodes.html
--- a/content/canvas/test/webgl/conformance/glsl/misc/glsl-function-nodes.html
+++ b/content/canvas/test/webgl/conformance/glsl/misc/glsl-function-nodes.html
@@ -117,17 +117,18 @@ function init()
     var bufFunction = new Uint8Array(width * height * 4);
     var bufMacro = new Uint8Array(width * height * 4);
 
     if (drawAndRead("canvasFunction", "vshaderFunction", bufFunction) == false ||
         drawAndRead("canvasMacro", "vshaderMacro", bufMacro) == false) {
         testFailed("Setup failed");
     } else {
         if (compareRendering(bufFunction, bufMacro, 4) == false)
-            testFailed("Rendering results are different");
+            testFailedRender("Rendering results are different", bufMacro,
+                             bufFunction, width, height);
         else
             testPassed("Rendering results are the same");
     }
 }
 
 init();
 successfullyParsed = true;
 </script>
diff --git a/content/canvas/test/webgl/conformance/misc/uninitialized-test.html b/content/canvas/test/webgl/conformance/misc/uninitialized-test.html
--- a/content/canvas/test/webgl/conformance/misc/uninitialized-test.html
+++ b/content/canvas/test/webgl/conformance/misc/uninitialized-test.html
@@ -56,17 +56,19 @@ function checkNonZeroPixels(texture, tex
     gl.readPixels(0, 0, texWidth, texHeight, gl.RGBA, gl.UNSIGNED_BYTE, data);
 
     var k = 0;
     for (var y = 0; y < texHeight; ++y) {
         for (var x = 0; x < texWidth; ++x) {
             var index = (y * texWidth + x) * 4;
             if (x >= skipX && x < skipX + skipWidth && y >= skipY && y < skipY + skipHeight) {
                 if (data[index] != skipR || data[index + 1] != skipG || data[index + 2] != skipB || data[index + 3] != skipA) {
-                    testFailed("non-zero pixel values are wrong");
+                    testFailed("non-zero pixel values are wrong at (" + x + ", " + y + "), data was (" +
+                               data[index] + "," + data[index + 1] + "," + data[index + 2] + "," + data[index + 3] +
+                               ") should have been (" + skipR + "," + skipG + "," + skipB + "," + skipA + ")");
                     return;
                 }
             } else {
                 for (var i = 0; i < 4; ++i) {
                     if (data[index + i] != 0)
                         k++;
                 }
             }
diff --git a/content/canvas/test/webgl/conformance/resources/webgl-test-utils.js b/content/canvas/test/webgl/conformance/resources/webgl-test-utils.js
--- a/content/canvas/test/webgl/conformance/resources/webgl-test-utils.js
+++ b/content/canvas/test/webgl/conformance/resources/webgl-test-utils.js
@@ -389,21 +389,29 @@ var drawQuad = function(gl, opt_color) {
 var checkCanvasRect = function(gl, x, y, width, height, color, msg, errorRange) {
   errorRange = errorRange || 0;
   var buf = new Uint8Array(width * height * 4);
   gl.readPixels(x, y, width, height, gl.RGBA, gl.UNSIGNED_BYTE, buf);
   for (var i = 0; i < width * height; ++i) {
     var offset = i * 4;
     for (var j = 0; j < color.length; ++j) {
       if (Math.abs(buf[offset + j] - color[j]) > errorRange) {
-        testFailed(msg);
         var was = buf[offset + 0].toString();
         for (j = 1; j < color.length; ++j) {
           was += "," + buf[offset + j];
         }
+
+        var cv = document.createElement('canvas');
+        cv.height = height;
+        cv.width = width;
+        var ctx = cv.getContext('2d');
+        ctx.fillStyle="rgba(" + color[0] + ", " + color[1] + ", " + color[2] + ", 255)";
+        ctx.fillRect(0, 0, width, height);
+        testFailedRender(msg, ctx, buf, width, height);
+
         debug('at (' + (i % width) + ', ' + Math.floor(i / width) +
               ') expected: ' + color + ' was ' + was);
         return;
       }
     }
   }
   testPassed(msg);
 };
diff --git a/content/canvas/test/webgl/resources/js-test-pre.js b/content/canvas/test/webgl/resources/js-test-pre.js
--- a/content/canvas/test/webgl/resources/js-test-pre.js
+++ b/content/canvas/test/webgl/resources/js-test-pre.js
@@ -81,16 +81,87 @@ function testPassed(msg)
     reportTestResultsToHarness(true, msg);
     debug('<span><span class="pass">PASS</span> ' + escapeHTML(msg) + '</span>');
 }
 
 function testFailed(msg)
 {
     reportTestResultsToHarness(false, msg);
     debug('<span><span class="fail">FAIL</span> ' + escapeHTML(msg) + '</span>');
+    dump('FAIL: ' + msg + '\n');
+
+    var stack = (new Error).stack.split('\n');
+    if (!stack.length) {
+        return;
+    }
+
+    dump('STACK TRACE: \n');
+
+    stack.pop();
+    var index = 0, frame, messages = new Array();
+    // Match all .html files and print out the line in them.
+    while (stack.length && index != -1) {
+        frame = stack.pop();
+        index = frame.indexOf(".html:");
+        if (index != -1) {
+            messages.unshift(frame);
+        }
+    }
+
+    // Print out the first stack frame in JS and then stop.
+    if (stack.length) {
+        messages.unshift(stack.pop());
+    }
+
+    for (message in messages) {
+        dump(messages[message] + '\n');
+    }
+}
+
+function testFailedRender(msg, ref, test, width, height) 
+{
+    var refData;
+    if (typeof ref.getImageData == 'function') {
+        refData = ref.canvas.toDataURL();
+    } else {
+        refData = arrayToURLData(ref, width, height);
+    }
+
+    var testData;
+    if (typeof test.getImageData == 'function') {
+        testData = test.canvas.toDataURL();
+    } else {
+        testData = arrayToURLData(test, width, height);
+    }
+    
+    testFailed(msg);
+
+    var data = 'REFTEST TEST-DEBUG-INFO | ' + msg + ' | image comparison (==)\n' +
+               'REFTEST   IMAGE 1 (TEST): ' + testData + '\n' +
+               'REFTEST   IMAGE 2 (REFERENCE): ' + refData;
+    dump('FAIL: ' + data + '\n');
+    dump('To view the differences between these image renderings, go to the following link: https://hg.mozilla.org/mozilla-central/raw-file/tip/layout/tools/reftest/reftest-analyzer.xhtml#log=' +
+    encodeURIComponent(encodeURIComponent(data)) + '\n');
+}
+
+function arrayToURLData(buf, width, height)
+{
+    var cv = document.createElement('canvas');
+    cv.height = height;
+    cv.width = width;
+    var ctx = cv.getContext('2d');
+    var imgd = ctx.getImageData(0, 0, width, height);
+    for (i = 0; i < height * width; ++i) {
+        offset = i * 4;
+        for (j = 0; j < 4; j++) {
+            imgd.data[offset + j] = buf[offset + j];
+        }
+    }
+    ctx.putImageData(imgd, 0, 0);
+    return cv.toDataURL();
 }
 
 function areArraysEqual(_a, _b)
 {
     try {
         if (_a.length !== _b.length)
             return false;
         for (var i = 0; i < _a.length; i++)