1 files changed, 45 insertions, 0 deletions
diff --git a/dom/tests/browser/browser_cancel_keydown_keypress_event.js b/dom/tests/browser/browser_cancel_keydown_keypress_event.js
new file mode 100644
index 0000000000..d3414185c2
--- /dev/null
+++ b/dom/tests/browser/browser_cancel_keydown_keypress_event.js
@@ -0,0 +1,45 @@
+const URL =
+  "https://example.com/browser/dom/tests/browser/prevent_return_key.html";
+
+// Wait for alert dialog and dismiss it immediately.
+function awaitAndCloseAlertDialog() {
+  return new Promise(resolve => {
+    function onDialogShown(node) {
+      Services.obs.removeObserver(onDialogShown, "tabmodal-dialog-loaded");
+      let button = node.querySelector(".tabmodalprompt-button0");
+      button.click();
+      resolve();
+    }
+    Services.obs.addObserver(onDialogShown, "tabmodal-dialog-loaded");
+  });
+}
+
+add_task(async function() {
+  await SpecialPowers.pushPrefEnv({
+    set: [["prompts.contentPromptSubDialog", false]],
+  });
+
+  let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, URL);
+  let browser = tab.linkedBrowser;
+
+  // Focus and enter random text on input.
+  await SpecialPowers.spawn(browser, [], async function() {
+    let input = content.document.getElementById("input");
+    input.focus();
+    input.value = "abcd";
+  });
+
+  // Send return key (cross process) to submit the form implicitly.
+  let dialogShown = awaitAndCloseAlertDialog();
+  EventUtils.synthesizeKey("KEY_Enter");
+  await dialogShown;
+
+  // Check that the form should not have been submitted.
+  await SpecialPowers.spawn(browser, [], async function() {
+    let result = content.document.getElementById("result").innerHTML;
+    info("submit result: " + result);
+    is(result, "not submitted", "form should not have submitted");
+  });
+
+  gBrowser.removeCurrentTab();
+});