1 files changed, 71 insertions, 0 deletions
diff --git a/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_null.js b/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_null.js
new file mode 100644
index 0000000000..a98a2495c4
--- /dev/null
+++ b/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_null.js
@@ -0,0 +1,71 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+add_task(async function () {
+  await pushPref("devtools.chrome.enabled", true);
+  await addTab("about:blank");
+
+  info(`Open browser console with ctrl-shift-j`);
+  // we're using the browser console so we can check for error messages that would be
+  // caused by console code.
+  const opened = waitForBrowserConsole();
+  EventUtils.synthesizeKey("j", { accelKey: true, shiftKey: true }, window);
+  const hud = await opened;
+  const { jsterm } = hud;
+  const { autocompletePopup: popup } = jsterm;
+
+  info(`Clear existing messages`);
+  const onMessagesCleared = hud.ui.once("messages-cleared");
+  await clearOutput(hud);
+  await onMessagesCleared;
+
+  info(`Create a null variable`);
+  // Using the commands directly as we don't want to impact the UI state.
+  await hud.commands.scriptCommand.execute("globalThis.nullVar = null");
+
+  info(`Check completion suggestions for "null"`);
+  await setInputValueForAutocompletion(hud, "null");
+  ok(popup.isOpen, "popup is open");
+  const expectedPopupItems = ["null", "nullVar"];
+  ok(
+    hasExactPopupLabels(popup, expectedPopupItems),
+    "popup has expected items"
+  );
+
+  info(`Check completion suggestions for "null."`);
+  let onAutocompleteUpdated = jsterm.once("autocomplete-updated");
+  EventUtils.sendString(".", hud.iframeWindow);
+  await onAutocompleteUpdated;
+  is(popup.itemCount, 0, "popup has no items");
+
+  info(`Check completion suggestions for "null"`);
+  onAutocompleteUpdated = jsterm.once("autocomplete-updated");
+  EventUtils.synthesizeKey("KEY_Backspace", undefined, hud.iframeWindow);
+  await onAutocompleteUpdated;
+  is(popup.itemCount, 2, "popup has 2 items");
+
+  info(`Check completion suggestions for "nullVar"`);
+  onAutocompleteUpdated = jsterm.once("autocomplete-updated");
+  EventUtils.sendString("Var.", hud.iframeWindow);
+  await onAutocompleteUpdated;
+  is(popup.itemCount, 0, "popup has no items");
+  is(popup.isOpen, false, "popup is closed");
+
+  info(`Check that no error was logged`);
+  await waitFor(() => findErrorMessage(hud, "", ":not(.network)")).then(
+    message => {
+      ok(false, `Got error ${JSON.stringify(message.textContent)}`);
+    },
+    error => {
+      if (!error.message.includes("Failed waitFor")) {
+        throw error;
+      }
+      ok(true, `No error was logged`);
+    }
+  );
+
+  info(`Cleanup`);
+  await hud.commands.scriptCommand.execute("delete globalThis.nullVar");
+});