Bookmarks bar, tooltip should be seen only for folders with big names on macOS.

chrome/browser/ui/cocoa/bookmarks/bookmark_bar_folder_controller_unittest.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cmath>
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
 #import "chrome/browser/ui/cocoa/bookmarks/bookmark_bar_constants.h"
@@ skipping 1597 matching lines @@
   CGFloat pos = [folder indicatorPosForDragToPoint:targetPoint];
   EXPECT_CGFLOAT_EQ(targetPoint.y + yTopOffset, pos);
   pos = [folder indicatorPosForDragToPoint:[targetButton bottom]];
   targetButton = [folder buttonWithTitleEqualTo:@"2f2f"];
   EXPECT_CGFLOAT_EQ([targetButton top].y + yTopOffset, pos);
   pos = [folder indicatorPosForDragToPoint:NSMakePoint(10,0)];
   targetButton = [folder buttonWithTitleEqualTo:@"2f3b"];
   EXPECT_CGFLOAT_EQ([targetButton bottom].y - yBottomOffset, pos);
 }
 
+TEST_F(BookmarkBarFolderControllerMenuTest, FolderTooltips) {
+  BookmarkModel* model = BookmarkModelFactory::GetForBrowserContext(profile());
+  const BookmarkNode* otherBookmarks = model->other_node();
+  model->AddFolder(otherBookmarks, otherBookmarks->child_count(),
+                   ASCIIToUTF16("short_name"));
+  model->AddFolder(
+      otherBookmarks, otherBookmarks->child_count(),
+      ASCIIToUTF16("reallyReallyLongBookmarkNamereallyReallyLongBookmarkNamerea"
+                   "llyReallyLongBookmarkNamereallyReallyLongBookmarkName"));
+  BookmarkButton* otherButton = [bar_ otherBookmarksButton];
+  ASSERT_TRUE(otherButton);
+
+  [[otherButton target] openBookmarkFolderFromButton:otherButton];
+  BookmarkBarFolderController* folder = [bar_ folderController];
+  EXPECT_TRUE(folder);
+
+  NSArray* buttons = [folder buttons];
+  EXPECT_EQ(2U, [buttons count]);
+
+  for (BookmarkButton* btn in buttons) {
+    if ([[btn cell] cellSize].width >
+        bookmarks::kBookmarkMenuButtonMaximumWidth) {
+      EXPECT_TRUE([btn toolTip]);
+    } else {
+      EXPECT_FALSE([btn toolTip]);
+    }
+  }
+}
+
 @interface BookmarkBarControllerNoDelete : BookmarkBarController
 - (IBAction)deleteBookmark:(id)sender;
 @end
 
 @implementation BookmarkBarControllerNoDelete
 - (IBAction)deleteBookmark:(id)sender {
   // NOP
 }
 @end
 
@@ skipping 42 matching lines @@
   DeleteBookmark([folder parentButton], profile());
   EXPECT_FALSE([folder folderController]);
 }
 
 // TODO(jrg): draggingEntered: and draggingExited: trigger timers so
 // they are hard to test.  Factor out "fire timers" into routines
 // which can be overridden to fire immediately to make behavior
 // confirmable.
 // There is a similar problem with mouseEnteredButton: and
 // mouseExitedButton:.