diff --git a/src/calibre/db/tests/add_remove.py b/src/calibre/db/tests/add_remove.py
index a39a698f8b..b2da91cd60 100644
--- a/src/calibre/db/tests/add_remove.py
+++ b/src/calibre/db/tests/add_remove.py
@@ -218,14 +218,14 @@ class AddRemoveTest(BaseTest):
         authors = cache.fields['authors'].table
 
         # Delete a single book, with no formats and check cleaning
-        self.assertIn(_('Unknown'), set(itervalues(authors.id_map)))
+        self.assertIn('Unknown', set(itervalues(authors.id_map)))
         olen = len(authors.id_map)
-        item_id = {v:k for k, v in iteritems(authors.id_map)}[_('Unknown')]
+        item_id = {v:k for k, v in iteritems(authors.id_map)}['Unknown']
         cache.remove_books((3,))
         for c in (cache, self.init_cache()):
             table = c.fields['authors'].table
             self.assertNotIn(3, c.all_book_ids())
-            self.assertNotIn(_('Unknown'), set(itervalues(table.id_map)))
+            self.assertNotIn('Unknown', set(itervalues(table.id_map)))
             self.assertNotIn(item_id, table.asort_map)
             self.assertNotIn(item_id, table.alink_map)
             ae(len(table.id_map), olen-1)
diff --git a/src/calibre/db/tests/legacy.py b/src/calibre/db/tests/legacy.py
index 41f1af4e91..31b5eb519c 100644
--- a/src/calibre/db/tests/legacy.py
+++ b/src/calibre/db/tests/legacy.py
@@ -130,18 +130,18 @@ class LegacyTest(BaseTest):
                     ans[label] = tuple(set(x.split(',')) if x else x for x in ans[label])
                 if label == 'series_sort':
                     # The old db code did not take book language into account
-                    # when generating series_sort values (the first book has
-                    # lang=deu)
-                    ans[label] = ans[label][1:]
+                    # when generating series_sort values
+                    ans[label] = None
             return ans
 
+        db = self.init_legacy()
+        new_vals = get_values(db)
+        db.close()
+
         old = self.init_old()
         old_vals = get_values(old)
         old.close()
         old = None
-        db = self.init_legacy()
-        new_vals = get_values(db)
-        db.close()
         self.assertEqual(old_vals, new_vals)
 
     # }}}
diff --git a/src/calibre/db/tests/reading.py b/src/calibre/db/tests/reading.py
index 2dffd0d48f..fb78328e9b 100644
--- a/src/calibre/db/tests/reading.py
+++ b/src/calibre/db/tests/reading.py
@@ -12,10 +12,15 @@ from io import BytesIO
 from time import time
 
 from calibre.utils.date import utc_tz
+from calibre.utils.localization import calibre_langcode_to_name
 from calibre.db.tests.base import BaseTest
 from polyglot.builtins import iteritems, itervalues, range
 
 
+def p(x):
+    return datetime.datetime.strptime(x, '%Y-%m-%d').replace(tzinfo=utc_tz)
+
+
 class ReadingTest(BaseTest):
 
     def test_read(self):  # {{{
@@ -130,6 +135,9 @@ class ReadingTest(BaseTest):
         'Test sorting'
         cache = self.init_cache()
         ae = self.assertEqual
+
+        lmap = {x:cache.field_for('languages', x) for x in (1, 2, 3)}
+        lq = sorted(lmap, key=lambda x: calibre_langcode_to_name((lmap[x] or ('',))[0]))
         for field, order in iteritems({
             'title'  : [2, 1, 3],
             'authors': [2, 1, 3],
@@ -143,7 +151,7 @@ class ReadingTest(BaseTest):
             'timestamp': [2, 1, 3],
             'pubdate'  : [1, 2, 3],
             'publisher': [3, 2, 1],
-            'languages': [3, 2, 1],
+            'languages': lq,
             'comments': [3, 2, 1],
             '#enum' : [3, 2, 1],
             '#authors' : [3, 2, 1],
@@ -182,7 +190,6 @@ class ReadingTest(BaseTest):
             ae([2, 3, 1], cache.multisort([(field, False)], ids_to_sort=(1, 2, 3)))
 
         # Test tweak to sort dates by visible format
-        from calibre.utils.date import parse_only_date as p
         from calibre.utils.config_base import Tweak
         ae(cache.set_field('pubdate', {1:p('2001-3-3'), 2:p('2002-2-3'), 3:p('2003-1-3')}), {1, 2, 3})
         ae([1, 2, 3], cache.multisort([('pubdate', True)]))
@@ -285,7 +292,7 @@ class ReadingTest(BaseTest):
         oldvals = {query:set(old.search_getting_ids(query, '')) for query in (
             # Date tests
             'date:9/6/2011', 'date:true', 'date:false', 'pubdate:1/9/2011',
-            '#date:true', 'date:<100daysago', 'date:>9/6/2011',
+            '#date:true', 'date:<100_daysago', 'date:>9/6/2011',
             '#date:>9/1/2011', '#date:=2011',
 
             # Number tests
@@ -296,8 +303,8 @@ class ReadingTest(BaseTest):
             'series_index:<3',
 
             # Bool tests
-            '#yesno:true', '#yesno:false', '#yesno:yes', '#yesno:no',
-            '#yesno:empty',
+            '#yesno:true', '#yesno:false', '#yesno:_yes', '#yesno:_no',
+            '#yesno:_empty',
 
             # Keypair tests
             'identifiers:true', 'identifiers:false', 'identifiers:test',
@@ -632,14 +639,13 @@ class ReadingTest(BaseTest):
 
     def test_composites(self):  # {{{
         ' Test sorting and searching in composite columns '
-        from calibre.utils.date import parse_only_date as p
         cache = self.init_cache()
         cache.create_custom_column('mult', 'CC1', 'composite', True, display={'composite_template': 'b,a,c'})
         cache.create_custom_column('single', 'CC2', 'composite', False, display={'composite_template': 'b,a,c'})
         cache.create_custom_column('number', 'CC3', 'composite', False, display={'composite_template': '{#float}', 'composite_sort':'number'})
         cache.create_custom_column('size', 'CC4', 'composite', False, display={'composite_template': '{#float:human_readable()}', 'composite_sort':'number'})
         cache.create_custom_column('ccdate', 'CC5', 'composite', False,
-                                   display={'composite_template': '{pubdate:format_date(d-M-yy)}', 'composite_sort':'date'})
+                display={'composite_template': "{:'format_date(raw_field('pubdate'), 'dd-MM-yy')'}", 'composite_sort':'date'})
         cache.create_custom_column('bool', 'CC6', 'composite', False, display={'composite_template': '{#yesno}', 'composite_sort':'bool'})
         cache.create_custom_column('ccm', 'CC7', 'composite', True, display={'composite_template': '{#tags}'})
         cache.create_custom_column('ccp', 'CC8', 'composite', True, display={'composite_template': '{publisher}'})
@@ -659,7 +665,7 @@ class ReadingTest(BaseTest):
         self.assertEqual([1, 2, 3], cache.multisort([('#size', True)]))
 
         # Test date sorting
-        cache.set_field('pubdate', {1:p('2001-2-6'), 2:p('2001-10-6'), 3:p('2001-6-6')})
+        cache.set_field('pubdate', {1:p('2001-02-06'), 2:p('2001-10-06'), 3:p('2001-06-06')})
         self.assertEqual([1, 3, 2], cache.multisort([('#ccdate', True)]))
 
         # Test bool sorting
@@ -692,7 +698,7 @@ class ReadingTest(BaseTest):
         lm2.languages = ['eng']
         for mi, books in (
                 (Metadata('title one', ['author one']), {2}),
-                (Metadata(_('Unknown')), {3}),
+                (Metadata('Unknown', ['Unknown']), {3}),
                 (Metadata('title two', ['author one']), {1}),
                 (lm, {1}),
                 (lm2, set()),
diff --git a/src/calibre/db/tests/writing.py b/src/calibre/db/tests/writing.py
index e41b30c743..663e45f3fd 100644
--- a/src/calibre/db/tests/writing.py
+++ b/src/calibre/db/tests/writing.py
@@ -11,7 +11,7 @@ from collections import namedtuple
 from functools import partial
 from io import BytesIO
 
-from calibre.ebooks.metadata import author_to_author_sort
+from calibre.ebooks.metadata import author_to_author_sort, title_sort
 from calibre.utils.date import UNDEFINED_DATE
 from calibre.db.tests.base import BaseTest, IMG
 from polyglot.builtins import iteritems, itervalues
@@ -237,7 +237,7 @@ class WritingTest(BaseTest):
         for name in ('authors', '#authors'):
             f = cache.fields[name]
             ae(len(f.table.id_map), 3)
-            af(cache.set_field(name, {3:None if name == 'authors' else 'Unknown'}))
+            af(cache.set_field(name, {3:'Unknown'}))
             ae(cache.set_field(name, {3:'Kovid Goyal & Divok Layog'}), {3})
             ae(cache.set_field(name, {1:'', 2:'An, Author'}), {1,2})
             cache2 = self.init_cache(cl)
@@ -245,9 +245,9 @@ class WritingTest(BaseTest):
                 ae(len(c.fields[name].table.id_map), 4 if name =='authors' else 3)
                 ae(c.field_for(name, 3), ('Kovid Goyal', 'Divok Layog'))
                 ae(c.field_for(name, 2), ('An, Author',))
-                ae(c.field_for(name, 1), ('Unknown',) if name=='authors' else ())
+                ae(c.field_for(name, 1), (_('Unknown'),) if name=='authors' else ())
                 if name == 'authors':
-                    ae(c.field_for('author_sort', 1), author_to_author_sort('Unknown'))
+                    ae(c.field_for('author_sort', 1), author_to_author_sort(_('Unknown')))
                     ae(c.field_for('author_sort', 2), author_to_author_sort('An, Author'))
                     ae(c.field_for('author_sort', 3), author_to_author_sort('Kovid Goyal') + ' & ' + author_to_author_sort('Divok Layog'))
             del cache2
@@ -292,8 +292,8 @@ class WritingTest(BaseTest):
         ae(sf('title', {1:'The Moose', 2:'Cat'}), {1, 2})
         cache2 = self.init_cache(cl)
         for c in (cache, cache2):
-            ae(c.field_for('sort', 1), 'Moose, The')
-            ae(c.field_for('sort', 2), 'Cat')
+            ae(c.field_for('sort', 1), title_sort('The Moose'))
+            ae(c.field_for('sort', 2), title_sort('Cat'))
 
         # Test setting with the same value repeated
         ae(sf('tags', {3: ('a', 'b', 'a')}), {3})
diff --git a/src/calibre/library/caches.py b/src/calibre/library/caches.py
index 922c59d26b..8904cfea8a 100644
--- a/src/calibre/library/caches.py
+++ b/src/calibre/library/caches.py
@@ -346,7 +346,7 @@ class ResultCache(SearchQueryParser):  # {{{
     untrans_daysago_len = len('_daysago')
 
     def get_dates_matches(self, location, query, candidates):
-        matches = set([])
+        matches = set()
         if len(query) < 2:
             return matches
 
@@ -395,7 +395,7 @@ class ResultCache(SearchQueryParser):  # {{{
             qd = now()
             field_count = 2
         elif query.endswith(self.local_daysago) or query.endswith(self.untrans_daysago):
-            num = query[0:-(self.local_daysago_len if query.endswith(self.local_daysago) else self.untrans_daysago_len)]
+            num = query[0:-(self.untrans_daysago_len if query.endswith(self.untrans_daysago) else self.local_daysago_len)]
             try:
                 qd = now() - timedelta(int(num))
             except:
diff --git a/src/calibre/srv/tests/ajax.py b/src/calibre/srv/tests/ajax.py
index 915eae11de..acdc2f4668 100644
--- a/src/calibre/srv/tests/ajax.py
+++ b/src/calibre/srv/tests/ajax.py
@@ -69,9 +69,9 @@ class ContentTest(LibraryBaseTest):
             self.ae(r.status, OK)
             self.ae(data, xdata)
             names = {x['name']:x['url'] for x in data}
-            for q in ('Newest', 'All books', 'Tags', 'Series', 'Authors', 'Enum', 'Composite Tags'):
+            for q in (_('Newest'), _('All books'), _('Tags'), _('Authors'), _('Enum'), _('Composite Tags')):
                 self.assertIn(q, names)
-            r, data = request(names['Tags'], prefix='')
+            r, data = request(names[_('Tags')], prefix='')
             self.ae(r.status, OK)
             names = {x['name']:x['url'] for x in data['items']}
             self.ae(set(names), set('Tag One,Tag Two,News'.split(',')))
@@ -128,7 +128,7 @@ class ContentTest(LibraryBaseTest):
             ae(set(r(url_for('/ajax/search?query=id:2'))['book_ids']), {2})
             ae(set(r(url_for('/ajax/search?vl=1'))['book_ids']), {1})
             data = make_request(conn, '/ajax/search', username='inv', password='test', prefix='', method='GET')[1]
-            ae(data['bad_restriction'], 'Invalid syntax. Expected a lookup name or a word')
+            ae(data['bad_restriction'], _('Invalid syntax. Expected a lookup name or a word'))
 
             # books.py
             nf(url_for('/book-manifest', book_id=3, fmt='TXT'))