1 files changed, 65 insertions, 0 deletions
diff --git a/testing/web-platform/tests/fullscreen/trusted-click.js b/testing/web-platform/tests/fullscreen/trusted-click.js
new file mode 100644
index 0000000000..51fbce7ee4
--- /dev/null
+++ b/testing/web-platform/tests/fullscreen/trusted-click.js
@@ -0,0 +1,65 @@
+/**
+ * Invokes callback from a trusted click event, avoiding interception by fullscreen element.
+ *
+ * @param {Element} container - Element where button will be created and clicked.
+ */
+function trusted_click(container = document.body) {
+    var document = container.ownerDocument;
+    var button = document.createElement("button");
+    button.textContent = "click to continue test";
+    button.style.display = "block";
+    button.style.fontSize = "20px";
+    button.style.padding = "10px";
+    button.addEventListener("click", () => {
+        button.remove();
+    });
+    container.appendChild(button);
+    if (window.top !== window) test_driver.set_test_context(window.top);
+    // Race them for manually testing...
+    return Promise.race([
+        test_driver.click(button),
+        new Promise((resolve) => {
+            button.addEventListener("click", resolve);
+        }),
+    ]);
+}
+
+// Invokes element.requestFullscreen() from a trusted click.
+async function trusted_request(element = document.body, whereToCreateButton = null) {
+    await trusted_click(whereToCreateButton ?? element.parentNode ?? element);
+    return element.requestFullscreen();
+}
+
+/**
+ * Used to await a fullscreen change event, once.
+ *
+ * @param {EventTarget} target
+ * @returns
+ */
+function fullScreenChange(target = document) {
+    return new Promise((resolve) =>
+        target.addEventListener("fullscreenchange", resolve, { once: true })
+    );
+}
+
+/**
+ * Sets up a message event listener, and returns a promise that resolves
+ * when the message from the iframe is received.
+ *
+ * @param {HTMLIFrameElement} iframe
+ * @returns {Promise<object>}
+ */
+function promiseMessage(iframe) {
+    return new Promise((resolve) => {
+        window.addEventListener(
+            "message",
+            (e) => {
+                if (e.data?.report.api === "fullscreen") {
+                    resolve(e.data);
+                }
+            },
+            { once: true }
+        );
+        iframe.contentWindow.postMessage({ action: "report" }, "*");
+    });
+}