chromium/src/third_party/blink/web_tests/fast/canvas/canvas-save-restore-with-path.html

<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script>
test(function(t) {
}, "This test ensures that paths are correctly handled over save/restore boundaries");

function pixelShouldBe(x, y, color) {
    assert_array_equals(context.getImageData(x, y, 1, 1).data, color);
}

var canvas = document.createElement("canvas");
canvas.width = 100;
canvas.height = 100;

var context = canvas.getContext("2d");
context.fillStyle = "red";
context.fillRect(0, 0, 100, 100);
context.fillStyle = "green";

// Test translate
context.beginPath();
context.save();
context.translate(100, 100);
context.rect(-100, -100, 50, 50);
context.restore();
context.fill();
pixelShouldBe(25, 25, [0, 128, 0, 255]);

// Test scale
context.beginPath();
context.save();
context.scale(2, 2);
context.rect(25, 0, 25, 25);
context.restore();
context.fill();
pixelShouldBe(75, 25, [0, 128, 0, 255]);
pixelShouldBe(75, 75, [255, 0, 0, 255]);

// Test rotate
context.beginPath();
context.save();
context.rotate(90/180 * Math.PI);
context.rect(50, -50, 50, 50);
context.restore();
context.fill();
pixelShouldBe(25, 75, [0, 128, 0, 255]);
pixelShouldBe(75, 75, [255, 0, 0, 255]);

// Test transform
context.beginPath();
context.save();
context.transform(1, 0, 0, 1, 50, 50);
context.rect(0, 0, 50, 50);
context.restore();
context.fill();
pixelShouldBe(75, 75, [0, 128, 0, 255]);
</script>