1 files changed, 56 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/forms/the-form-element/form-action-submission-with-base-url.html b/testing/web-platform/tests/html/semantics/forms/the-form-element/form-action-submission-with-base-url.html
new file mode 100644
index 0000000000..baee5500de
--- /dev/null
+++ b/testing/web-platform/tests/html/semantics/forms/the-form-element/form-action-submission-with-base-url.html
@@ -0,0 +1,56 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<title>form action="" attribute effect on submission</title>
+<link rel="author" title="Domenic Denicola" href="mailto:d@domenic.me">
+<link rel="help" href="https://html.spec.whatwg.org/multipage/forms.html#dom-fs-action">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<body>
+<script>
+"use strict";
+
+// promise_test instead of async_test because all tests use window.success, and so can't run at the same time.
+
+promise_test(t => {
+  return new Promise(resolve => {
+    window.success = t.step_func(locationLoaded => {
+      const expected = (new URL("resources/target/form-action-url-target.html?name=value", location.href)).href;
+      assert_equals(locationLoaded, expected);
+      resolve();
+    });
+
+    const iframe = document.createElement("iframe");
+    iframe.src = "resources/form-with-action-and-base.sub.html?action=form-action-url-target.html";
+    document.body.appendChild(iframe);
+  });
+}, "An action URL should be resolved relative to the document's base URL (not document URL)");
+
+promise_test(t => {
+  return new Promise(resolve => {
+    window.success = t.step_func(locationLoaded => {
+      const expected = (new URL("resources/form-with-action-and-base.sub.html?name=value", location.href)).href;
+      assert_equals(locationLoaded, expected);
+      resolve();
+    });
+
+    const iframe = document.createElement("iframe");
+    iframe.src = "resources/form-with-action-and-base.sub.html?action=";
+    document.body.appendChild(iframe);
+  });
+}, "An empty-string action should submit the form to its containing document's URL (not its base URL)");
+
+promise_test(t => {
+  return new Promise(resolve => {
+    window.success = t.step_func(locationLoaded => {
+      const expected = (new URL("resources/form-no-action-with-base.html?name=value", location.href)).href;
+      assert_equals(locationLoaded, expected);
+      resolve();
+    });
+
+    const iframe = document.createElement("iframe");
+    iframe.src = "resources/form-no-action-with-base.html";
+    document.body.appendChild(iframe);
+  });
+}, "A missing action should submit the form to its containing document's URL (not its base URL)");
+</script>