1 files changed, 92 insertions, 0 deletions
diff --git a/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_width.js b/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_width.js
new file mode 100644
index 0000000000..e085841575
--- /dev/null
+++ b/devtools/client/webconsole/test/browser/browser_jsterm_autocomplete_width.js
@@ -0,0 +1,92 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Test that the autocomplete popup is resized when needed.
+
+const TEST_URI = `data:text/html;charset=utf-8,<!DOCTYPE html>
+<head>
+  <script>
+    /* Create prototype-less object so popup does not contain native
+     * Object prototype properties.
+     */
+    window.xx = Object.create(null, Object.getOwnPropertyDescriptors({
+      ["y".repeat(10)]: 1,
+      ["z".repeat(20)]: 2
+    }));
+    window.xxx = 1;
+  </script>
+</head>
+<body>Test</body>`;
+
+add_task(async function () {
+  const hud = await openNewTabAndConsole(TEST_URI);
+  const { jsterm } = hud;
+  const { autocompletePopup: popup } = jsterm;
+
+  info(`wait for completion suggestions for "xx"`);
+  await setInputValueForAutocompletion(hud, "xx");
+  ok(popup.isOpen, "popup is open");
+
+  const expectedPopupItems = ["xx", "xxx"];
+  ok(
+    hasExactPopupLabels(popup, expectedPopupItems),
+    "popup has expected items"
+  );
+
+  const originalWidth = popup._tooltip.container.clientWidth;
+  Assert.greaterOrEqual(
+    originalWidth,
+    getLongestLabelWidth(jsterm),
+    `popup (${originalWidth}px) is at least wider than the width of the longest list item (${getLongestLabelWidth(
+      jsterm
+    )}px)`
+  );
+
+  info(`wait for completion suggestions for "xx."`);
+  let onAutocompleteUpdated = jsterm.once("autocomplete-updated");
+  EventUtils.sendString(".");
+  await onAutocompleteUpdated;
+
+  ok(
+    hasExactPopupLabels(popup, ["y".repeat(10), "z".repeat(20)]),
+    "popup has expected items"
+  );
+  const newPopupWidth = popup._tooltip.container.clientWidth;
+  Assert.greaterOrEqual(
+    newPopupWidth,
+    originalWidth,
+    `The popup width was updated (${originalWidth}px -> ${newPopupWidth}px)`
+  );
+  Assert.greaterOrEqual(
+    newPopupWidth,
+    getLongestLabelWidth(jsterm),
+    `popup (${newPopupWidth}px) is at least wider than the width of the longest list item (${getLongestLabelWidth(
+      jsterm
+    )}px)`
+  );
+
+  info(`wait for completion suggestions for "xx"`);
+  onAutocompleteUpdated = jsterm.once("autocomplete-updated");
+  EventUtils.synthesizeKey("KEY_Backspace");
+  await onAutocompleteUpdated;
+
+  is(
+    popup._tooltip.container.clientWidth,
+    originalWidth,
+    "popup is back to its original width"
+  );
+
+  info("Close autocomplete popup");
+  await closeAutocompletePopup(hud);
+});
+
+function getLongestLabelWidth(jsterm) {
+  return (
+    jsterm._inputCharWidth *
+    getAutocompletePopupLabels(jsterm.autocompletePopup).sort(
+      (a, b) => a < b
+    )[0].length
+  );
+}