Merge branch 'safari-fly-out-fix' into 'master'

Fix the fly-out menu in the sidebar not displaying in Safari

Closes #36441

See merge request !13445

app/assets/javascripts/fly_out_nav.js

 import Cookies from 'js-cookie';
 import bp from './breakpoints';
 
+const HIDE_INTERVAL_TIMEOUT = 300;
+const IS_OVER_CLASS = 'is-over';
+const IS_ABOVE_CLASS = 'is-above';
+const IS_SHOWING_FLY_OUT_CLASS = 'is-showing-fly-out';
+let currentOpenMenu = null;
+let menuCornerLocs;
+let timeoutId;
+
+export const mousePos = [];
+
+export const setOpenMenu = (menu = null) => { currentOpenMenu = menu; };
+
+export const slope = (a, b) => (b.y - a.y) / (b.x - a.x);
+
+let headerHeight = 50;
+
+export const getHeaderHeight = () => headerHeight;
+
 export const canShowActiveSubItems = (el) => {
   const isHiddenByMedia = bp.getBreakpointSize() === 'sm' || bp.getBreakpointSize() === 'md';
 
@@ -10,8 +28,28 @@ export const canShowActiveSubItems = (el) => {
 
   return true;
 };
+
 export const canShowSubItems = () => bp.getBreakpointSize() === 'sm' || bp.getBreakpointSize() === 'md' || bp.getBreakpointSize() === 'lg';
 
+export const getHideSubItemsInterval = () => {
+  if (!currentOpenMenu) return 0;
+
+  const currentMousePos = mousePos[mousePos.length - 1];
+  const prevMousePos = mousePos[0];
+  const currentMousePosY = currentMousePos.y;
+  const [menuTop, menuBottom] = menuCornerLocs;
+
+  if (currentMousePosY < menuTop.y ||
+    currentMousePosY > menuBottom.y) return 0;
+
+  if (slope(prevMousePos, menuBottom) < slope(currentMousePos, menuBottom) &&
+    slope(prevMousePos, menuTop) > slope(currentMousePos, menuTop)) {
+    return HIDE_INTERVAL_TIMEOUT;
+  }
+
+  return 0;
+};
+
 export const calculateTop = (boundingRect, outerHeight) => {
   const windowHeight = window.innerHeight;
   const bottomOverflow = windowHeight - (boundingRect.top + outerHeight);
@@ -20,45 +58,120 @@ export const calculateTop = (boundingRect, outerHeight) => {
     boundingRect.top;
 };
 
-export const showSubLevelItems = (el) => {
-  const subItems = el.querySelector('.sidebar-sub-level-items');
+export const hideMenu = (el) => {
+  if (!el) return;
 
-  if (!subItems || !canShowSubItems() || !canShowActiveSubItems(el)) return;
+  const parentEl = el.parentNode;
 
-  subItems.style.display = 'block';
-  el.classList.add('is-showing-fly-out');
-  el.classList.add('is-over');
+  el.style.display = ''; // eslint-disable-line no-param-reassign
+  el.style.transform = ''; // eslint-disable-line no-param-reassign
+  el.classList.remove(IS_ABOVE_CLASS);
+  parentEl.classList.remove(IS_OVER_CLASS);
+  parentEl.classList.remove(IS_SHOWING_FLY_OUT_CLASS);
+
+  setOpenMenu();
+};
 
+export const moveSubItemsToPosition = (el, subItems) => {
   const boundingRect = el.getBoundingClientRect();
   const top = calculateTop(boundingRect, subItems.offsetHeight);
   const isAbove = top < boundingRect.top;
 
   subItems.classList.add('fly-out-list');
-  subItems.style.transform = `translate3d(0, ${Math.floor(top)}px, 0)`;
+  subItems.style.transform = `translate3d(0, ${Math.floor(top) - headerHeight}px, 0)`; // eslint-disable-line no-param-reassign
+
+  const subItemsRect = subItems.getBoundingClientRect();
+
+  menuCornerLocs = [
+    {
+      x: subItemsRect.left, // left position of the sub items
+      y: subItemsRect.top, // top position of the sub items
+    },
+    {
+      x: subItemsRect.left, // left position of the sub items
+      y: subItemsRect.top + subItemsRect.height, // bottom position of the sub items
+    },
+  ];
 
   if (isAbove) {
-    subItems.classList.add('is-above');
+    subItems.classList.add(IS_ABOVE_CLASS);
   }
 };
 
-export const hideSubLevelItems = (el) => {
+export const showSubLevelItems = (el) => {
+  const subItems = el.querySelector('.sidebar-sub-level-items');
+
+  if (!canShowSubItems() || !canShowActiveSubItems(el)) return;
+
+  el.classList.add(IS_OVER_CLASS);
+
+  if (!subItems) return;
+
+  subItems.style.display = 'block';
+  el.classList.add(IS_SHOWING_FLY_OUT_CLASS);
+
+  setOpenMenu(subItems);
+  moveSubItemsToPosition(el, subItems);
+};
+
+export const mouseEnterTopItems = (el) => {
+  clearTimeout(timeoutId);
+
+  timeoutId = setTimeout(() => {
+    if (currentOpenMenu) hideMenu(currentOpenMenu);
+
+    showSubLevelItems(el);
+  }, getHideSubItemsInterval());
+};
+
+export const mouseLeaveTopItem = (el) => {
   const subItems = el.querySelector('.sidebar-sub-level-items');
 
-  if (!subItems || !canShowSubItems() || !canShowActiveSubItems(el)) return;
+  if (!canShowSubItems() || !canShowActiveSubItems(el) ||
+    (subItems && subItems === currentOpenMenu)) return;
+
+  el.classList.remove(IS_OVER_CLASS);
+};
+
+export const documentMouseMove = (e) => {
+  mousePos.push({
+    x: e.clientX,
+    y: e.clientY,
+  });
 
-  el.classList.remove('is-showing-fly-out');
-  el.classList.remove('is-over');
-  subItems.style.display = '';
-  subItems.style.transform = '';
-  subItems.classList.remove('is-above');
+  if (mousePos.length > 6) mousePos.shift();
 };
 
 export default () => {
-  const items = [...document.querySelectorAll('.sidebar-top-level-items > li')]
-    .filter(el => el.querySelector('.sidebar-sub-level-items'));
+  const sidebar = document.querySelector('.sidebar-top-level-items');
+
+  if (!sidebar) return;
+
+  const items = [...sidebar.querySelectorAll('.sidebar-top-level-items > li')];
+
+  sidebar.addEventListener('mouseleave', () => {
+    clearTimeout(timeoutId);
+
+    timeoutId = setTimeout(() => {
+      if (currentOpenMenu) hideMenu(currentOpenMenu);
+    }, getHideSubItemsInterval());
+  });
+
+  headerHeight = document.querySelector('.nav-sidebar').offsetTop;
 
   items.forEach((el) => {
-    el.addEventListener('mouseenter', e => showSubLevelItems(e.currentTarget));
-    el.addEventListener('mouseleave', e => hideSubLevelItems(e.currentTarget));
+    const subItems = el.querySelector('.sidebar-sub-level-items');
+
+    if (subItems) {
+      subItems.addEventListener('mouseleave', () => {
+        clearTimeout(timeoutId);
+        hideMenu(currentOpenMenu);
+      });
+    }
+
+    el.addEventListener('mouseenter', e => mouseEnterTopItems(e.currentTarget));
+    el.addEventListener('mouseleave', e => mouseLeaveTopItem(e.currentTarget));
   });
+
+  document.addEventListener('mousemove', documentMouseMove);
 };

app/assets/stylesheets/new_sidebar.scss

@@ -97,9 +97,9 @@ $new-sidebar-collapsed-width: 50px;
   top: $header-height;
   bottom: 0;
   left: 0;
-  overflow: auto;
   background-color: $gray-normal;
   box-shadow: inset -2px 0 0 $border-color;
+  transform: translate3d(0, 0, 0);
 
   &.sidebar-icons-only {
     width: $new-sidebar-collapsed-width;
@@ -175,6 +175,12 @@ $new-sidebar-collapsed-width: 50px;
   }
 }
 
+.nav-sidebar-inner-scroll {
+  height: 100%;
+  width: 100%;
+  overflow: auto;
+}
+
 .with-performance-bar .nav-sidebar {
   top: $header-height + $performance-bar-height;
 }

app/views/layouts/nav/_new_group_sidebar.html.haml

 .nav-sidebar{ class: ("sidebar-icons-only" if collapsed_sidebar?) }
-  .context-header
-    = link_to group_path(@group), title: @group.name do
-      .avatar-container.s40.group-avatar
-        = image_tag group_icon(@group), class: "avatar s40 avatar-tile"
-      .group-title
-        = @group.name
-  %ul.sidebar-top-level-items
-    = nav_link(path: ['groups#show', 'groups#activity', 'groups#subgroups'], html_options: { class: 'home' }) do
-      = link_to group_path(@group), title: 'Group overview' do
-        .nav-icon-container
-          = custom_icon('project')
-        %span.nav-item-name
-          Overview
-
-      %ul.sidebar-sub-level-items
-        = nav_link(path: ['groups#show', 'groups#subgroups'], html_options: { class: 'home' }) do
-          = link_to group_path(@group), title: 'Group details' do
-            %span
-              Details
-
-        = nav_link(path: 'groups#activity') do
-          = link_to activity_group_path(@group), title: 'Activity' do
-            %span
-              Activity
-
-    = nav_link(path: ['groups#issues', 'labels#index', 'milestones#index']) do
-      = link_to issues_group_path(@group), title: 'Issues' do
-        .nav-icon-container
-          = custom_icon('issues')
-        %span.nav-item-name
-          - issues = IssuesFinder.new(current_user, group_id: @group.id, state: 'opened').execute
-          Issues
-        %span.badge.count= number_with_delimiter(issues.count)
-
-      %ul.sidebar-sub-level-items
-        = nav_link(path: 'groups#issues', html_options: { class: 'home' }) do
-          = link_to issues_group_path(@group), title: 'List' do
-            %span
-              List
+  .nav-sidebar-inner-scroll
+    .context-header
+      = link_to group_path(@group), title: @group.name do
+        .avatar-container.s40.group-avatar
+          = image_tag group_icon(@group), class: "avatar s40 avatar-tile"
+        .group-title
+          = @group.name
+    %ul.sidebar-top-level-items
+      = nav_link(path: ['groups#show', 'groups#activity', 'groups#subgroups'], html_options: { class: 'home' }) do
+        = link_to group_path(@group), title: 'Group overview' do
+          .nav-icon-container
+            = custom_icon('project')
+          %span.nav-item-name
+            Overview
 
-        = nav_link(path: 'labels#index') do
-          = link_to group_labels_path(@group), title: 'Labels' do
-            %span
-              Labels
+        %ul.sidebar-sub-level-items
+          = nav_link(path: ['groups#show', 'groups#subgroups'], html_options: { class: 'home' }) do
+            = link_to group_path(@group), title: 'Group details' do
+              %span
+                Details
 
-        = nav_link(path: 'milestones#index') do
-          = link_to group_milestones_path(@group), title: 'Milestones' do
-            %span
-              Milestones
+          = nav_link(path: 'groups#activity') do
+            = link_to activity_group_path(@group), title: 'Activity' do
+              %span
+                Activity
 
-    = nav_link(path: 'groups#merge_requests') do
-      = link_to merge_requests_group_path(@group), title: 'Merge Requests' do
-        .nav-icon-container
-          = custom_icon('mr_bold')
-        %span.nav-item-name
-          - merge_requests = MergeRequestsFinder.new(current_user, group_id: @group.id, state: 'opened', non_archived: true).execute
-          Merge Requests
-        %span.badge.count= number_with_delimiter(merge_requests.count)
-    = nav_link(path: 'group_members#index') do
-      = link_to group_group_members_path(@group), title: 'Members' do
-        .nav-icon-container
-          = custom_icon('members')
-        %span.nav-item-name
-          Members
-    - if current_user && can?(current_user, :admin_group, @group)
-      = nav_link(path: %w[groups#projects groups#edit ci_cd#show]) do
-        = link_to edit_group_path(@group), title: 'Settings' do
+      = nav_link(path: ['groups#issues', 'labels#index', 'milestones#index']) do
+        = link_to issues_group_path(@group), title: 'Issues' do
           .nav-icon-container
-            = custom_icon('settings')
+            = custom_icon('issues')
           %span.nav-item-name
-            Settings
+            - issues = IssuesFinder.new(current_user, group_id: @group.id, state: 'opened').execute
+            Issues
+          %span.badge.count= number_with_delimiter(issues.count)
+
         %ul.sidebar-sub-level-items
-          = nav_link(path: 'groups#edit') do
-            = link_to edit_group_path(@group), title: 'General' do
+          = nav_link(path: 'groups#issues', html_options: { class: 'home' }) do
+            = link_to issues_group_path(@group), title: 'List' do
               %span
-                General
+                List
 
-          = nav_link(path: 'groups#projects') do
-            = link_to projects_group_path(@group), title: 'Projects' do
+          = nav_link(path: 'labels#index') do
+            = link_to group_labels_path(@group), title: 'Labels' do
               %span
-                Projects
+                Labels
 
-          = nav_link(controller: :ci_cd) do
-            = link_to group_settings_ci_cd_path(@group), title: 'CI / CD' do
+          = nav_link(path: 'milestones#index') do
+            = link_to group_milestones_path(@group), title: 'Milestones' do
               %span
-                CI / CD
+                Milestones
+
+      = nav_link(path: 'groups#merge_requests') do
+        = link_to merge_requests_group_path(@group), title: 'Merge Requests' do
+          .nav-icon-container
+            = custom_icon('mr_bold')
+          %span.nav-item-name
+            - merge_requests = MergeRequestsFinder.new(current_user, group_id: @group.id, state: 'opened', non_archived: true).execute
+            Merge Requests
+          %span.badge.count= number_with_delimiter(merge_requests.count)
+      = nav_link(path: 'group_members#index') do
+        = link_to group_group_members_path(@group), title: 'Members' do
+          .nav-icon-container
+            = custom_icon('members')
+          %span.nav-item-name
+            Members
+      - if current_user && can?(current_user, :admin_group, @group)
+        = nav_link(path: %w[groups#projects groups#edit ci_cd#show]) do
+          = link_to edit_group_path(@group), title: 'Settings' do
+            .nav-icon-container
+              = custom_icon('settings')
+            %span.nav-item-name
+              Settings
+          %ul.sidebar-sub-level-items
+            = nav_link(path: 'groups#edit') do
+              = link_to edit_group_path(@group), title: 'General' do
+                %span
+                  General
+
+            = nav_link(path: 'groups#projects') do
+              = link_to projects_group_path(@group), title: 'Projects' do
+                %span
+                  Projects
+
+            = nav_link(controller: :ci_cd) do
+              = link_to group_settings_ci_cd_path(@group), title: 'CI / CD' do
+                %span
+                  CI / CD
 
-  = render 'shared/sidebar_toggle_button'
+    = render 'shared/sidebar_toggle_button'

app/views/layouts/nav/_new_profile_sidebar.html.haml

 .nav-sidebar{ class: ("sidebar-icons-only" if collapsed_sidebar?) }
-  .context-header
-    = link_to profile_path, title: 'Profile Settings' do
-      .avatar-container.s40.settings-avatar
-        = icon('user')
-      .project-title User Settings
-  %ul.sidebar-top-level-items
-    = nav_link(path: 'profiles#show', html_options: {class: 'home'}) do
+  .nav-sidebar-inner-scroll
+    .context-header
       = link_to profile_path, title: 'Profile Settings' do
-        .nav-icon-container
-          = custom_icon('profile')
-        %span.nav-item-name
-          Profile
-    = nav_link(controller: [:accounts, :two_factor_auths]) do
-      = link_to profile_account_path, title: 'Account' do
-        .nav-icon-container
-          = custom_icon('account')
-        %span.nav-item-name
-          Account
-    - if current_application_settings.user_oauth_applications?
-      = nav_link(controller: 'oauth/applications') do
-        = link_to applications_profile_path, title: 'Applications' do
+        .avatar-container.s40.settings-avatar
+          = icon('user')
+        .project-title User Settings
+    %ul.sidebar-top-level-items
+      = nav_link(path: 'profiles#show', html_options: {class: 'home'}) do
+        = link_to profile_path, title: 'Profile Settings' do
           .nav-icon-container
-            = custom_icon('applications')
+            = custom_icon('profile')
           %span.nav-item-name
-            Applications
-    = nav_link(controller: :chat_names) do
-      = link_to profile_chat_names_path, title: 'Chat' do
-        .nav-icon-container
-          = custom_icon('chat')
-        %span.nav-item-name
-          Chat
-    = nav_link(controller: :personal_access_tokens) do
-      = link_to profile_personal_access_tokens_path, title: 'Access Tokens' do
-        .nav-icon-container
-          = custom_icon('access_tokens')
-        %span.nav-item-name
-          Access Tokens
-    = nav_link(controller: :emails) do
-      = link_to profile_emails_path, title: 'Emails' do
-        .nav-icon-container
-          = custom_icon('emails')
-        %span.nav-item-name
-          Emails
-    - unless current_user.ldap_user?
-      = nav_link(controller: :passwords) do
-        = link_to edit_profile_password_path, title: 'Password' do
+            Profile
+      = nav_link(controller: [:accounts, :two_factor_auths]) do
+        = link_to profile_account_path, title: 'Account' do
           .nav-icon-container
-            = custom_icon('lock')
+            = custom_icon('account')
           %span.nav-item-name
-            Password
-    = nav_link(controller: :notifications) do
-      = link_to profile_notifications_path, title: 'Notifications' do
-        .nav-icon-container
-          = custom_icon('notifications')
-        %span.nav-item-name
-          Notifications
+            Account
+      - if current_application_settings.user_oauth_applications?
+        = nav_link(controller: 'oauth/applications') do
+          = link_to applications_profile_path, title: 'Applications' do
+            .nav-icon-container
+              = custom_icon('applications')
+            %span.nav-item-name
+              Applications
+      = nav_link(controller: :chat_names) do
+        = link_to profile_chat_names_path, title: 'Chat' do
+          .nav-icon-container
+            = custom_icon('chat')
+          %span.nav-item-name
+            Chat
+      = nav_link(controller: :personal_access_tokens) do
+        = link_to profile_personal_access_tokens_path, title: 'Access Tokens' do
+          .nav-icon-container
+            = custom_icon('access_tokens')
+          %span.nav-item-name
+            Access Tokens
+      = nav_link(controller: :emails) do
+        = link_to profile_emails_path, title: 'Emails' do
+          .nav-icon-container
+            = custom_icon('emails')
+          %span.nav-item-name
+            Emails
+      - unless current_user.ldap_user?
+        = nav_link(controller: :passwords) do
+          = link_to edit_profile_password_path, title: 'Password' do
+            .nav-icon-container
+              = custom_icon('lock')
+            %span.nav-item-name
+              Password
+      = nav_link(controller: :notifications) do
+        = link_to profile_notifications_path, title: 'Notifications' do
+          .nav-icon-container
+            = custom_icon('notifications')
+          %span.nav-item-name
+            Notifications
 
-    = nav_link(controller: :keys) do
-      = link_to profile_keys_path, title: 'SSH Keys' do
-        .nav-icon-container
-          = custom_icon('key')
-        %span.nav-item-name
-          SSH Keys
-    = nav_link(controller: :gpg_keys) do
-      = link_to profile_gpg_keys_path, title: 'GPG Keys' do
-        .nav-icon-container
-          = custom_icon('key_2')
-        %span.nav-item-name
-          GPG Keys
-    = nav_link(controller: :preferences) do
-      = link_to profile_preferences_path, title: 'Preferences' do
-        .nav-icon-container
-          = custom_icon('preferences')
-        %span.nav-item-name
-          Preferences
-    = nav_link(path: 'profiles#audit_log') do
-      = link_to audit_log_profile_path, title: 'Authentication log' do
-        .nav-icon-container
-          = custom_icon('authentication_log')
-        %span.nav-item-name
-          Authentication log
+      = nav_link(controller: :keys) do
+        = link_to profile_keys_path, title: 'SSH Keys' do
+          .nav-icon-container
+            = custom_icon('key')
+          %span.nav-item-name
+            SSH Keys
+      = nav_link(controller: :gpg_keys) do
+        = link_to profile_gpg_keys_path, title: 'GPG Keys' do
+          .nav-icon-container
+            = custom_icon('key_2')
+          %span.nav-item-name
+            GPG Keys
+      = nav_link(controller: :preferences) do
+        = link_to profile_preferences_path, title: 'Preferences' do
+          .nav-icon-container
+            = custom_icon('preferences')
+          %span.nav-item-name
+            Preferences
+      = nav_link(path: 'profiles#audit_log') do
+        = link_to audit_log_profile_path, title: 'Authentication log' do
+          .nav-icon-container
+            = custom_icon('authentication_log')
+          %span.nav-item-name
+            Authentication log
 
-  = render 'shared/sidebar_toggle_button'
+    = render 'shared/sidebar_toggle_button'

spec/javascripts/fly_out_nav_spec.js

 import Cookies from 'js-cookie';
 import {
   calculateTop,
-  hideSubLevelItems,
   showSubLevelItems,
   canShowSubItems,
   canShowActiveSubItems,
+  mouseEnterTopItems,
+  mouseLeaveTopItem,
+  setOpenMenu,
+  mousePos,
+  getHideSubItemsInterval,
+  documentMouseMove,
+  getHeaderHeight,
 } from '~/fly_out_nav';
 import bp from '~/breakpoints';
 
@@ -18,11 +24,14 @@ describe('Fly out sidebar navigation', () => {
     document.body.appendChild(el);
 
     spyOn(bp, 'getBreakpointSize').and.callFake(() => breakpointSize);
+
+    setOpenMenu(null);
   });
 
   afterEach(() => {
-    el.remove();
+    document.body.innerHTML = '';
     breakpointSize = 'lg';
+    mousePos.length = 0;
   });
 
   describe('calculateTop', () => {
@@ -49,61 +58,153 @@ describe('Fly out sidebar navigation', () => {
     });
   });
 
-  describe('hideSubLevelItems', () => {
+  describe('getHideSubItemsInterval', () => {
     beforeEach(() => {
-      el.innerHTML = '<div class="sidebar-sub-level-items"></div>';
+      el.innerHTML = '<div class="sidebar-sub-level-items" style="position: fixed; top: 0; left: 100px; height: 150px;"></div>';
     });
 
-    it('hides subitems', () => {
-      hideSubLevelItems(el);
+    it('returns 0 if currentOpenMenu is nil', () => {
+      expect(
+        getHideSubItemsInterval(),
+      ).toBe(0);
+    });
+
+    it('returns 0 when mouse above sub-items', () => {
+      showSubLevelItems(el);
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: el.getBoundingClientRect().top,
+      });
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: el.getBoundingClientRect().top - 50,
+      });
 
       expect(
-        el.querySelector('.sidebar-sub-level-items').style.display,
-      ).toBe('');
+        getHideSubItemsInterval(),
+      ).toBe(0);
     });
 
-    it('does not hude subitems on mobile', () => {
-      breakpointSize = 'xs';
+    it('returns 0 when mouse is below sub-items', () => {
+      const subItems = el.querySelector('.sidebar-sub-level-items');
 
-      hideSubLevelItems(el);
+      showSubLevelItems(el);
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: el.getBoundingClientRect().top,
+      });
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: (el.getBoundingClientRect().top - subItems.getBoundingClientRect().height) + 50,
+      });
 
       expect(
-        el.querySelector('.sidebar-sub-level-items').style.display,
-      ).not.toBe('none');
+        getHideSubItemsInterval(),
+      ).toBe(0);
     });
 
-    it('removes is-over class', () => {
+    it('returns 300 when mouse is moved towards sub-items', () => {
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: el.getBoundingClientRect().top,
+      });
+      showSubLevelItems(el);
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left + 20,
+        clientY: el.getBoundingClientRect().top + 10,
+      });
+      console.log(el);
+
+      expect(
+        getHideSubItemsInterval(),
+      ).toBe(300);
+    });
+  });
+
+  describe('mouseLeaveTopItem', () => {
+    beforeEach(() => {
       spyOn(el.classList, 'remove');
+    });
 
-      hideSubLevelItems(el);
+    it('removes is-over class if currentOpenMenu is null', () => {
+      mouseLeaveTopItem(el);
 
       expect(
         el.classList.remove,
       ).toHaveBeenCalledWith('is-over');
     });
 
-    it('removes is-above class from sub-items', () => {
-      const subItems = el.querySelector('.sidebar-sub-level-items');
+    it('removes is-over class if currentOpenMenu is null & there are sub-items', () => {
+      el.innerHTML = '<div class="sidebar-sub-level-items" style="position: absolute;"></div>';
+
+      mouseLeaveTopItem(el);
+
+      expect(
+        el.classList.remove,
+      ).toHaveBeenCalledWith('is-over');
+    });
+
+    it('does not remove is-over class if currentOpenMenu is the passed in sub-items', () => {
+      el.innerHTML = '<div class="sidebar-sub-level-items" style="position: absolute;"></div>';
+
+      setOpenMenu(el.querySelector('.sidebar-sub-level-items'));
+      mouseLeaveTopItem(el);
+
+      expect(
+        el.classList.remove,
+      ).not.toHaveBeenCalled();
+    });
+  });
 
-      spyOn(subItems.classList, 'remove');
+  describe('mouseEnterTopItems', () => {
+    beforeEach(() => {
+      jasmine.clock().install();
 
-      hideSubLevelItems(el);
+      el.innerHTML = '<div class="sidebar-sub-level-items" style="position: absolute; top: 0; left: 100px; height: 200px;"></div>';
+    });
+
+    afterEach(() => {
+      jasmine.clock().uninstall();
+    });
+
+    it('shows sub-items after 0ms if no menu is open', () => {
+      mouseEnterTopItems(el);
 
       expect(
-        subItems.classList.remove,
-      ).toHaveBeenCalledWith('is-above');
+        getHideSubItemsInterval(),
+      ).toBe(0);
+
+      jasmine.clock().tick(0);
+
+      expect(
+        el.querySelector('.sidebar-sub-level-items').style.display,
+      ).toBe('block');
     });
 
-    it('does nothing if el has no sub-items', () => {
-      el.innerHTML = '';
+    it('shows sub-items after 300ms if a menu is currently open', () => {
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left,
+        clientY: el.getBoundingClientRect().top,
+      });
 
-      spyOn(el.classList, 'remove');
+      setOpenMenu(el.querySelector('.sidebar-sub-level-items'));
+
+      documentMouseMove({
+        clientX: el.getBoundingClientRect().left + 20,
+        clientY: el.getBoundingClientRect().top + 10,
+      });
 
-      hideSubLevelItems(el);
+      mouseEnterTopItems(el);
 
       expect(
-        el.classList.remove,
-      ).not.toHaveBeenCalledWith();
+        getHideSubItemsInterval(),
+      ).toBe(300);
+
+      jasmine.clock().tick(300);
+
+      expect(
+        el.querySelector('.sidebar-sub-level-items').style.display,
+      ).toBe('block');
     });
   });
 
@@ -132,7 +233,7 @@ describe('Fly out sidebar navigation', () => {
       ).not.toBe('block');
     });
 
-    it('does not shows sub-items', () => {
+    it('shows sub-items', () => {
       showSubLevelItems(el);
 
       expect(
@@ -146,7 +247,7 @@ describe('Fly out sidebar navigation', () => {
 
       expect(
         subItems.style.transform,
-      ).toBe(`translate3d(0px, ${Math.floor(el.getBoundingClientRect().top)}px, 0px)`);
+      ).toBe(`translate3d(0px, ${Math.floor(el.getBoundingClientRect().top) - getHeaderHeight()}px, 0px)`);
     });
 
     it('sets is-above when element is above', () => {