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Test Info: Warnings
- This test has a WPT meta file that expects 1 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /html/canvas/element/manual/draw-element-image/error-conditions.tentative.html - WPT Dashboard Interop Dashboard
<!DOCTYPE html>
<title>Tests that error conditions cause exceptions</title>
<link rel="author" href="mailto:chrishtr@chromium.org">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/html/canvas/resources/wait-for-canvas-paint.js"></script>
<style>
#child {
width: 100px;
height: 100px;
background: green;
}
#canvas {
background: grey;
}
</style>
<canvas id=canvas width="200" height="200" layoutsubtree>
<div id=child>
<div id=grandchild></div>
</div>
</canvas>
<canvas id=canvaswithoutlayout layoutsubtree>
<div id=child2></div>
</div>
</canvas>
<script>
promise_test(async () => {
await waitForCanvasPaint(canvas);
assert_throws_dom("InvalidStateError",
() => canvas.getContext("2d").drawElementImage(grandchild, 20, 30),
"Can't draw non-direct children.");
canvas.toggleAttribute("layoutsubtree"); // Remove attribute.
assert_throws_dom("InvalidStateError",
() => canvas.getContext("2d").drawElementImage(child, 20, 30),
"Can't draw canvas children if layoutsubtree is not specified.");
assert_throws_dom("InvalidStateError",
() => canvas.captureElementImage(child),
"Can't capture element image if layoutsubtree is not specified.");
assert_throws_dom("InvalidStateError",
() => canvas.getElementTransform(child, new DOMMatrix()),
"Can't get element transform if layoutsubtree is not specified.");
canvas.toggleAttribute("layoutsubtree"); // Add attribute.
await waitForCanvasPaint(canvas);
// Should not throw an exception.
canvas.getContext("2d").drawElementImage(child, 20, 30);
let img = canvas.captureElementImage(child);
canvas.getElementTransform(child, new DOMMatrix());
canvaswithoutlayout.removeAttribute("layoutsubtree");
assert_throws_dom("InvalidStateError",
() => canvaswithoutlayout.getContext("2d").drawElementImage(
child2, 20, 30),
"Can't draw canvas children if layoutsubtree is not specified.");
assert_throws_dom("InvalidStateError",
() => canvaswithoutlayout.captureElementImage(child2),
"Can't capture element image if layoutsubtree is not specified.");
assert_throws_dom("InvalidStateError",
() => canvaswithoutlayout.getElementTransform(child2, new DOMMatrix()),
"Can't get element transform if layoutsubtree is not specified.");
// Also test wrong children exceptions
assert_throws_dom("InvalidStateError",
() => canvas.captureElementImage(grandchild),
"Can't capture non-direct children.");
assert_throws_dom("InvalidStateError",
() => canvas.getElementTransform(grandchild, new DOMMatrix()),
"Can't get transform for non-direct children.");
});
</script>
</html>