buffers/search: fix handling malformed queries

3 files changed, 27 insertions, 16 deletions

diff --git a/alot/buffers/search.py b/alot/buffers/search.py
index bf758c95..20c0ae47 100644
--- a/alot/buffers/search.py
+++ b/alot/buffers/search.py
@@ -5,9 +5,9 @@
 import asyncio
 
 import urwid
-from notmuch2 import NotmuchError
 
 from .buffer import Buffer
+from ..db.errors        import QueryError
 from ..db.sort          import NAME as SORT_NAME
 from ..settings.const import settings
 from ..widgets.search import ThreadlineWidget
@@ -163,20 +163,24 @@ class SearchBuffer(Buffer):
         self._result_count = None
         self._thread_count = None
 
+        threads    = self.dbman.get_threads(self.querystring, self.sort_order,
+                                            exclude_tags)
+        threadlist = IterWalker(threads, self.dbman)
+
+        # check that the query is well-formed
         try:
-            threads = self.dbman.get_threads(self.querystring, self.sort_order,
-                                             exclude_tags)
-        except NotmuchError:
+            threadlist[0]
+        except IndexError:
+            # empty result list, no problem
+            pass
+        except QueryError:
             self.ui.notify('malformed query string: %s' % self.querystring,
                            'error')
-            self.listbox = urwid.ListBox([])
-            self.body = self.listbox
-            return
-
-        self.threadlist = IterWalker(threads, self.dbman)
+            threadlist = []
 
-        self.listbox = urwid.ListBox(self.threadlist)
-        self.body = self.listbox
+        self.threadlist = threadlist
+        self.listbox    = urwid.ListBox(self.threadlist)
+        self.body       = self.listbox
 
     def get_selected_threadline(self):
         """
diff --git a/alot/db/errors.py b/alot/db/errors.py
index bd2564f9..d5fd9f9a 100644
--- a/alot/db/errors.py
+++ b/alot/db/errors.py
@@ -12,6 +12,10 @@ class DatabaseROError(DatabaseError):
     """cannot write to read-only database"""
     pass
 
+class QueryError(DatabaseError):
+    """malformed query"""
+    pass
+
 
 class NonexistantObjectError(DatabaseError):
 
diff --git a/alot/db/manager.py b/alot/db/manager.py
index e57af181..aa67ed40 100644
--- a/alot/db/manager.py
+++ b/alot/db/manager.py
@@ -11,9 +11,8 @@ import os
 
 from notmuch2 import Database, NotmuchError
 
-from .errors import DatabaseError
-from .errors import DatabaseROError
-from .errors import NonexistantObjectError
+from .errors import (DatabaseError, DatabaseROError, NonexistantObjectError,
+                     QueryError)
 from .sort   import ORDER
 from .thread import Thread
 from ..settings.const import settings
@@ -214,8 +213,12 @@ class DBManager:
         with self._db_ro() as db:
             exclude_tags = self._exclude_tags | exclude_tags
 
-            for t in db.threads(querystring, sort = sort, exclude_tags = exclude_tags):
-                yield t.threadid
+            try:
+                for t in db.threads(querystring, sort = sort,
+                                    exclude_tags = exclude_tags):
+                    yield t.threadid
+            except NotmuchError as e:
+                raise QueryError from e
 
     async def startup(self):
         self._write_queue = asyncio.Queue()