1 files changed, 34 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/canvas/offscreen/layers/2d.layer.malformed-operations.createPattern.html b/testing/web-platform/tests/html/canvas/offscreen/layers/2d.layer.malformed-operations.createPattern.html
new file mode 100644
index 0000000000..a206e64ceb
--- /dev/null
+++ b/testing/web-platform/tests/html/canvas/offscreen/layers/2d.layer.malformed-operations.createPattern.html
@@ -0,0 +1,34 @@
+<!DOCTYPE html>
+<!-- DO NOT EDIT! This test has been generated by /html/canvas/tools/gentest.py. -->
+<title>OffscreenCanvas test: 2d.layer.malformed-operations.createPattern</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/html/canvas/resources/canvas-tests.js"></script>
+
+<h1>2d.layer.malformed-operations.createPattern</h1>
+<p class="desc">Check that exceptions are thrown for operations that are malformed while layers are open.</p>
+
+
+<script>
+var t = async_test("Check that exceptions are thrown for operations that are malformed while layers are open.");
+var t_pass = t.done.bind(t);
+var t_fail = t.step_func(function(reason) {
+    throw reason;
+});
+t.step(function() {
+
+  var canvas = new OffscreenCanvas(200, 200);
+  var ctx = canvas.getContext('2d');
+
+  // Shouldn't throw on its own.
+  ctx.createPattern(canvas, 'repeat');
+  // Make sure the exception isn't caused by calling the function twice.
+  ctx.createPattern(canvas, 'repeat');
+  // Calling again inside a layer should throw.
+  ctx.beginLayer();
+  assert_throws_dom("InvalidStateError",
+                    () => ctx.createPattern(canvas, 'repeat'));
+  t.done();
+
+});
+</script>