reverted the JS timeout code

improved specs so that they pass

app/assets/javascripts/fly_out_nav.js

-let hideTimeoutInterval = 0;
-let hideTimeout;
-let subitems;
-
-export const getHideTimeoutInterval = () => hideTimeoutInterval;
-
-export const hideAllSubItems = () => {
-  subitems.forEach((el) => {
-    el.parentNode.classList.remove('is-over');
-    el.style.display = 'none'; // eslint-disable-line no-param-reassign
-  });
-};
-
 export const calculateTop = (boundingRect, outerHeight) => {
   const windowHeight = window.innerHeight;
   const bottomOverflow = windowHeight - (boundingRect.top + outerHeight);
@@ -24,14 +11,8 @@ export const showSubLevelItems = (el) => {
   if (!$subitems) return;
-  hideAllSubItems();
-
-  if (el.classList.contains('is-over')) {
-    clearTimeout(hideTimeout);
-  } else {
-    $subitems.style.display = 'block';
-    el.classList.add('is-over');
-  }
+  $subitems.style.display = 'block';
+  el.classList.add('is-over');
   const boundingRect = el.getBoundingClientRect();
   const top = calculateTop(boundingRect, $subitems.offsetHeight);
@@ -46,37 +27,20 @@ export const showSubLevelItems = (el) => {
 export const hideSubLevelItems = (el) => {
   const $subitems = el.querySelector('.sidebar-sub-level-items');
-  const hideFn = () => {
-    el.classList.remove('is-over');
-    $subitems.style.display = 'none';
-    $subitems.classList.remove('is-above');
-    hideTimeoutInterval = 0;
-  };
-
-  if ($subitems && hideTimeoutInterval) {
-    hideTimeout = setTimeout(hideFn, hideTimeoutInterval);
-  } else if ($subitems) {
-    hideFn();
-  }
-};
-export const setMouseOutTimeout = (el) => {
-  if (el.closest('.sidebar-sub-level-items')) {
-    hideTimeoutInterval = 250;
-  } else {
-    hideTimeoutInterval = 0;
-  }
+  if (!$subitems) return;
+  el.classList.remove('is-over');
+  $subitems.style.display = 'none';
+  $subitems.classList.remove('is-above');
 };
 export default () => {
-  const items = [...document.querySelectorAll('.sidebar-top-level-items > li:not(.active)')];
-  subitems = [...document.querySelectorAll('.sidebar-top-level-items > li:not(.active) .sidebar-sub-level-items')];
+  const items = [...document.querySelectorAll('.sidebar-top-level-items > li:not(.active)')]
+    .filter(el => el.querySelector('.sidebar-sub-level-items'));
   items.forEach((el) => {
     el.addEventListener('mouseenter', e => showSubLevelItems(e.currentTarget));
     el.addEventListener('mouseleave', e => hideSubLevelItems(e.currentTarget));
   });
-
-  subitems.forEach(el => el.addEventListener('mouseleave', e => setMouseOutTimeout(e.target)));
 };

app/assets/stylesheets/new_sidebar.scss

@@ -226,10 +226,10 @@ $new-sidebar-width: 220px;
           &::before {
             content: "";
             position: absolute;
-            top: -20px;
-            bottom: -20px;
+            top: -30px;
+            bottom: -30px;
             left: 0;
-            right: -20px;
+            right: -30px;
             z-index: -1;
           }

spec/javascripts/fly_out_nav_spec.js

 import {
   calculateTop,
-  setMouseOutTimeout,
-  getHideTimeoutInterval,
   hideSubLevelItems,
   showSubLevelItems,
 } from '~/fly_out_nav';
@@ -41,26 +39,6 @@ describe('Fly out sidebar navigation', () => {
     });
   });
-  describe('setMouseOutTimeout', () => {
-    it('sets hideTimeoutInterval to 150 when inside sub items', () => {
-      el.innerHTML = '<div class="sidebar-sub-level-items"><div class="js-test"></div></div>';
-
-      setMouseOutTimeout(el.querySelector('.js-test'));
-
-      expect(
-        getHideTimeoutInterval(),
-      ).toBe(150);
-    });
-
-    it('resets hideTimeoutInterval when not inside sub items', () => {
-      setMouseOutTimeout(el);
-
-      expect(
-        getHideTimeoutInterval(),
-      ).toBe(0);
-    });
-  });
-
   describe('hideSubLevelItems', () => {
     beforeEach(() => {
       el.innerHTML = '<div class="sidebar-sub-level-items"></div>';
@@ -142,16 +120,17 @@ describe('Fly out sidebar navigation', () => {
     it('sets is-above when element is above', () => {
       const subItems = el.querySelector('.sidebar-sub-level-items');
-      subItems.style.height = '5000px';
+      subItems.style.height = `${window.innerHeight + el.offsetHeight}px`;
+      subItems.style.position = 'absolute';
       el.style.position = 'relative';
-      el.style.top = '1000px';
-      spyOn(el.classList, 'add');
+      el.style.top = `${window.innerHeight - el.offsetHeight}px`;
+      spyOn(subItems.classList, 'add');
       showSubLevelItems(el);
       expect(
-        el.classList.add,
+        subItems.classList.add,
       ).toHaveBeenCalledWith('is-above');
     });
   });