1 files changed, 36 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/forms/the-input-element/defaultValue-clobbering.html b/testing/web-platform/tests/html/semantics/forms/the-input-element/defaultValue-clobbering.html
new file mode 100644
index 0000000000..41ff967c19
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+++ b/testing/web-platform/tests/html/semantics/forms/the-input-element/defaultValue-clobbering.html
@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<link rel="author" title="Joey Arhar" href="mailto:jarhar@chromium.org">
+<meta name="assert" content="Assigning to defaultValue does not modify text a user has already typed in.">
+
+<!-- This behavior is not explicitly specified. -->
+
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/testdriver.js"></script>
+<script src="/resources/testdriver-vendor.js"></script>
+
+<div>
+  email with leading whitespace: <input id=emailinput type=email>
+</div>
+<div>
+  number with trailing incomplete exponent: <input id=numberinput type=number>
+</div>
+
+<script>
+promise_test(async () => {
+  await test_driver.send_keys(emailinput, '  user');
+  assert_false(emailinput.validity.valid, '"  user" should not be a valid value for type=email.');
+
+  emailinput.defaultValue = emailinput.value;
+  assert_false(emailinput.validity.valid, 'Assigning to defaultValue should not affect input.validity.');
+}, 'Visible value and validity should not be affected when assigning to the defaultValue property for type=email.');
+
+promise_test(async () => {
+  await test_driver.send_keys(numberinput, '123e');
+  assert_false(numberinput.validity.valid, '"123e" should not be a valid value for type=number.');
+
+  numberinput.defaultValue = numberinput.value;
+  assert_false(numberinput.validity.valid, 'Assigning to defaultValue should not affect input.validity.');
+}, 'Visible value and validity should not be affected when assigning to the defaultValue property for type=number.');
+</script>