1 files changed, 50 insertions, 0 deletions
diff --git a/testing/web-platform/tests/xhr/overridemimetype-edge-cases.window.js b/testing/web-platform/tests/xhr/overridemimetype-edge-cases.window.js
new file mode 100644
index 0000000000..3f57e9a48f
--- /dev/null
+++ b/testing/web-platform/tests/xhr/overridemimetype-edge-cases.window.js
@@ -0,0 +1,50 @@
+const testURL = "resources/status.py?type=" + encodeURIComponent("text/plain;charset=windows-1252") + "&content=%C2%F0";
+
+async_test(t => {
+  const client = new XMLHttpRequest();
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseText, "\uFFFD\uFFFD");
+  });
+  client.overrideMimeType("text/plain;charset=UTF-8");
+  client.open("GET", testURL);
+  client.send();
+}, "overrideMimeType() is not reset by open(), basic");
+
+async_test(t => {
+  const client = new XMLHttpRequest();
+  let secondTime = false;
+  client.onload = t.step_func(() => {
+    if(!secondTime) {
+      assert_equals(client.responseText, "\uFFFD\uFFFD");
+      secondTime = true;
+      client.open("GET", testURL);
+      client.send();
+    } else {
+      assert_equals(client.responseText, "\uFFFD\uFFFD");
+      t.done();
+    }
+  });
+  client.open("GET", testURL);
+  client.overrideMimeType("text/plain;charset=UTF-8")
+  client.send();
+}, "overrideMimeType() is not reset by open()");
+
+async_test(t => {
+  const client = new XMLHttpRequest();
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseText, "Âð")
+  });
+  client.open("GET", testURL);
+  client.overrideMimeType("text/xml");
+  client.send();
+}, "If charset is not overridden by overrideMimeType() the original continues to be used");
+
+async_test(t => {
+  const client = new XMLHttpRequest();
+  client.onload = t.step_func_done(() => {
+    assert_equals(client.responseText, "\uFFFD\uFFFD")
+  });
+  client.open("GET", testURL);
+  client.overrideMimeType("text/plain;charset=342");
+  client.send();
+}, "Charset can be overridden by overrideMimeType() with a bogus charset");