Revert "Remove broken test for notmuch config parsing"

This reverts commit 1359aba.

tests/settings/test_manager.py

@@ -12,7 +12,7 @@
 from unittest import mock
 
 from alot.settings.manager import SettingsManager
-from alot.settings.errors import NoMatchingAccount
+from alot.settings.errors import ConfigError, NoMatchingAccount
 
 from .. import utilities
 
@@ -32,6 +32,18 @@ def test_reading_synchronize_flags_from_notmuch_config(self):
         actual = manager.get_notmuch_setting('maildir', 'synchronize_flags')
         self.assertTrue(actual)
 
+    def test_parsing_notmuch_config_with_non_bool_synchronize_flag_fails(self):
+        with tempfile.NamedTemporaryFile(mode='w+', delete=False) as f:
+            f.write(textwrap.dedent("""\
+                [maildir]
+                synchronize_flags = not bool
+                """))
+        self.addCleanup(os.unlink, f.name)
+
+        with self.assertRaises(ConfigError):
+            manager = SettingsManager()
+            manager.read_notmuch_config(f.name)
+
     def test_reload_notmuch_config(self):
         with tempfile.NamedTemporaryFile(mode='w+', delete=False) as f:
             f.write(textwrap.dedent("""\