1 files changed, 41 insertions, 0 deletions
diff --git a/testing/web-platform/tests/xhr/overridemimetype-invalid-mime-type.htm b/testing/web-platform/tests/xhr/overridemimetype-invalid-mime-type.htm
new file mode 100644
index 0000000000..506aff8419
--- /dev/null
+++ b/testing/web-platform/tests/xhr/overridemimetype-invalid-mime-type.htm
@@ -0,0 +1,41 @@
+<!doctype html>
+<title>XMLHttpRequest: overrideMimeType() and invalid MIME types</title>
+<meta charset="utf-8">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<link rel="help" href="https://xhr.spec.whatwg.org/#the-overridemimetype()-method">
+<div id="log"></div>
+<script>
+async_test(t => {
+  const client = new XMLHttpRequest()
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseText, "ÿ")
+    assert_equals(client.getResponseHeader("Content-Type"), "text/html;charset=windows-1252")
+  })
+  client.open("GET", "resources/status.py?type=" + encodeURIComponent("text/html;charset=windows-1252") + "&content=%FF")
+  client.overrideMimeType("bogus")
+  client.send()
+}, "Bogus MIME type does not override encoding")
+
+async_test(t => {
+  const client = new XMLHttpRequest()
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseText, "ÿ")
+    assert_equals(client.getResponseHeader("Content-Type"), "text/html;charset=windows-1252")
+  })
+  client.open("GET", "resources/status.py?type=" + encodeURIComponent("text/html;charset=windows-1252") + "&content=%FF")
+  client.overrideMimeType("bogus;charset=Shift_JIS")
+  client.send()
+}, "Bogus MIME type does not override encoding, 2")
+
+async_test(t => {
+  const client = new XMLHttpRequest()
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseXML, null)
+    assert_equals(client.getResponseHeader("Content-Type"), "text/xml")
+  })
+  client.open("GET", "resources/status.py?type=" + encodeURIComponent("text/xml") + "&content=" + encodeURIComponent("<x/>"))
+  client.overrideMimeType("bogus")
+  client.send()
+}, "Bogus MIME type does override MIME type")
+</script>