From aea66db0189619472115ec183ed472d2ffe199ef Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 13 Mar 2014 08:52:58 +0530
Subject: [PATCH] Show the search expression for the virtual library in a
 tooltip when hovering over the tab for the virtual library. Fixes #1291691
 [[Enhancement] VL search expression tooltip on
 hover](https://bugs.launchpad.net/calibre/+bug/1291691)

---
 src/calibre/gui2/init.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/calibre/gui2/init.py b/src/calibre/gui2/init.py
index 7c952ebaf3..2a626f784a 100644
--- a/src/calibre/gui2/init.py
+++ b/src/calibre/gui2/init.py
@@ -315,7 +315,8 @@ class VLTabs(QTabBar):  # {{{
     def rebuild(self):
         self.currentChanged.disconnect(self.tab_changed)
         db = self.current_db
-        virt_libs = frozenset(db.prefs.get('virtual_libraries', {}))
+        vl_map = db.prefs.get('virtual_libraries', {})
+        virt_libs = frozenset(vl_map)
         hidden = frozenset(db.prefs['virt_libs_hidden'])
         if hidden - virt_libs:
             db.prefs['virt_libs_hidden'] = list(hidden.intersection(virt_libs))
@@ -328,6 +329,9 @@ class VLTabs(QTabBar):  # {{{
         order = {x:i for i, x in enumerate(order)}
         for i, vl in enumerate(sorted(virt_libs, key=lambda x:(order.get(x, 0), sort_key(x)))):
             self.addTab(vl.replace('&', '&&') or _('All books'))
+            sexp = vl_map.get(vl, None)
+            if sexp is not None:
+                self.setTabToolTip(i, _('Search expression for this virtual library:') + '\n\n' + sexp)
             self.setTabData(i, vl)
             if vl == current_lib:
                 current_idx = i