Make sure we set the error message in the json as defined in the test

jail2ban/__init__.py

@@ -88,19 +88,28 @@ def create_app():
         name = untaint(PAT_NAME, name)
         app.logger.info(f'Flushing table f2b-{name}'
                         f' in anchor f2b-jail/{remote_user}')
+        reply = {'anchor': f'f2b-jail/{remote_user}',
+                        'table': f'f2b-{name}',
+                        'operation': 'list'}
+        try:
             res = pfctl_table_op('f2b-jail/{remote_user}',
                                  table='f2b-{name}',
                                  operation='show',
                                  verbose=True)
+        except CalledProcessError as err:
+            if err.stderr.find(b'pfctl: Table does not exist.') > 0:
+                res = []
+                reply.update({'error': f'\'{name}\' is not a known fail2ban jail'})
+            else:
+                raise err
+
         result = [entry.groupdict() for entry in
                   re.finditer(_PFCTL_TABLE_PAT,
                               '\n'.join([x.decode('ascii') for x in res]),
                               re.MULTILINE|re.VERBOSE)]
+        reply.update({'result': result})
 
-        return jsonify({'anchor': f'f2b-jail/{remote_user}',
+        return jsonify(reply), 200 if len(res) else 404
-                        'table': f'f2b-{name}',
-                        'operation': 'list',
-                        'result': result })
 
     @app.route("/register", methods=['PUT', 'DELETE'])
     @auth.login_required

tests/test_list.py

@@ -94,9 +94,13 @@ def test_list_nonexistent_table(client, mocker, valid_credentials):
     run_res.returncode = 255
     run_res.check_returncode = noop
 
-    # XXX raise a CalledProcessError here...
+    mocker.patch('jail2ban.pfctl.run',
-
+                 return_value=run_res,
-    mocker.patch('jail2ban.pfctl.run', return_value=run_res)
+                 side_effect=CalledProcessError(run_res.returncode,
+                                                'foobar',
+                                                 output=run_res.stdout,
+                                                 stderr=run_res.stderr)
+                 )
 
     response = client.get("/list/nonexistent",
                           headers={"Authorization":