1 files changed, 39 insertions, 0 deletions
diff --git a/testing/web-platform/tests/shadow-dom/declarative/declarative-parser-interaction.html b/testing/web-platform/tests/shadow-dom/declarative/declarative-parser-interaction.html
new file mode 100644
index 0000000000..f5ff13822b
--- /dev/null
+++ b/testing/web-platform/tests/shadow-dom/declarative/declarative-parser-interaction.html
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>Declarative Shadow DOM</title>
+<link rel="author" href="mailto:masonf@chromium.org">
+<link rel="help" href="https://github.com/whatwg/dom/issues/831">
+<link rel="help" href="https://crbug.com/1203645">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="support/helpers.js"></script>
+
+
+This test should not crash, and there should be two lines of text visible below.
+<x-1>
+    <template shadowrootmode="open">
+        <style>
+            @import 'non-existent.css';
+        </style>
+        <slot></slot>
+    </template>
+    <p>Line 1</p>
+</x-1>
+
+<x-2>
+    <template shadowrootmode="open">
+        <slot></slot>
+    </template>
+    <p>Line 2</p>
+</x-2>
+
+<script>
+  window.onload = function() {
+    const x1 = document.querySelector('x-1');
+    const x2 = document.querySelector('x-2');
+    test(() => {
+      assert_true(!!x1);
+      assert_true(!!x2);
+    }, 'Declarative Shadow DOM: Test for crashes and improper parsing');
+  }
+</script>