From 114e5cf3a771c64421108ae65e839e6c6b65b5f0 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Wed, 24 Jul 2013 18:55:39 +0530
Subject: [PATCH] Ensure that removing books does not cause errors when
 updating search caches

---
 src/calibre/db/cache.py  | 8 +++++---
 src/calibre/db/search.py | 5 +++++
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/calibre/db/cache.py b/src/calibre/db/cache.py
index 23e4498e72..ef4c8854b4 100644
--- a/src/calibre/db/cache.py
+++ b/src/calibre/db/cache.py
@@ -154,7 +154,7 @@ class Cache(object):
         self._search_api.update_or_clear(self, book_ids)
 
     @write_api
-    def clear_caches(self, book_ids=None, template_cache=True):
+    def clear_caches(self, book_ids=None, template_cache=True, search_cache=True):
         if template_cache:
             self._initialize_template_cache()  # Clear the formatter template cache
         for field in self.fields.itervalues():
@@ -165,7 +165,8 @@ class Cache(object):
                 self.format_metadata_cache.pop(book_id, None)
         else:
             self.format_metadata_cache.clear()
-        self._clear_search_caches(book_ids)
+        if search_cache:
+            self._clear_search_caches(book_ids)
 
     @write_api
     def reload_from_db(self, clear_caches=True):
@@ -1303,7 +1304,8 @@ class Cache(object):
                 continue  # Some fields like ondevice do not have tables
             else:
                 table.remove_books(book_ids, self.backend)
-        self._clear_caches(book_ids=book_ids, template_cache=False)
+        self._search_api.discard_books(book_ids)
+        self._clear_caches(book_ids=book_ids, template_cache=False, search_cache=False)
 
     @read_api
     def author_sort_strings_for_books(self, book_ids):
diff --git a/src/calibre/db/search.py b/src/calibre/db/search.py
index 3b441e6b2f..759b76fdb8 100644
--- a/src/calibre/db/search.py
+++ b/src/calibre/db/search.py
@@ -808,6 +808,11 @@ class Search(object):
         finally:
             sqp.dbcache = sqp.lookup_saved_search = None
 
+    def discard_books(self, book_ids):
+        book_ids = set(book_ids)
+        for query, result in self.cache:
+            result.difference_update(book_ids)
+
     def _update_caches(self, sqp, book_ids):
         book_ids = sqp.all_book_ids = set(book_ids)
         remove = set()