server_environment_ir_config_parameter: handle empty values better

server_environment_files_sample/dev/base.conf

@@ -9,3 +9,4 @@ lib_path = /myHome/lib/wkhtmltopdf-linux-i386-0-9-9
 
 [ir.config_parameter]
 ircp_from_config=config_value
+ircp_empty=

server_environment_ir_config_parameter/models/ir_config_parameter.py

@@ -20,6 +20,10 @@ class IrConfigParameter(models.Model):
             cr, uid, key, default=None, context=context)
         if serv_config.has_option(SECTION, key):
             cvalue = serv_config.get(SECTION, key)
+            if not cvalue:
+                raise UserError(_("Key %s is empty in "
+                                  "server_environment_file") %
+                                (key, ))
             if cvalue != value:
                 # we write in db on first access;
                 # should we have preloaded values in database at,

server_environment_ir_config_parameter/tests/test_server_environment_ircp.py

@@ -49,3 +49,9 @@ class TestEnv(common.SavepointCase):
         res.unlink()
         res = self.ICP.search([('key', '=', 'some.param')])
         self.assertFalse(res)
+
+    def test_empty(self):
+        """ Empty config values cause error """
+        with self.assertRaises(UserError):
+            self.ICP.get_param('ircp_empty')
+        self.assertEqual(self.ICP.get_param('ircp_nonexistant'), False)