fix rubocop offenses and provide NO_RESULT_CONDITION

app/helpers/additionals_queries_helper.rb

@@ -281,7 +281,7 @@ module AdditionalsQueriesHelper
   end
 
   def xlsx_hyperlink_cell?(token)
-    return if token.blank? || !token.is_a?(String)
+    return false if token.blank? || !token.is_a?(String)
 
     # Match http, https or ftp URL
     if %r{\A[fh]tt?ps?://}.match?(token) ||

app/models/additionals_query.rb

@@ -1,6 +1,9 @@
 # frozen_string_literal: true
 
 module AdditionalsQuery
+  NO_RESULT_CONDITION = '1=0'
+  WITH_TRUE_CONDITION = '1=1'
+
   def label_me_value
     self.class.label_me_value
   end
@@ -63,7 +66,7 @@ module AdditionalsQuery
       if ids.any?
         "#{queried_table_name}.id IN (#{ids.join ','})"
       else
-        '1=0'
+        NO_RESULT_CONDITION
       end
     else
       sql_for_field 'id', operator, value, queried_table_name, 'id'
@@ -222,7 +225,7 @@ module AdditionalsQuery
 
       "#{queried_table_name}.is_private = #{self.class.connection.quoted_true}"
     else
-      return '1=0' if value.count > 1
+      return NO_RESULT_CONDITION if value.count > 1
 
       "#{queried_table_name}.is_private = #{self.class.connection.quoted_false}"
     end

app/models/dashboard.rb

@@ -270,7 +270,7 @@ class Dashboard < ActiveRecord::Base
   end
 
   def deletable?(user = User.current)
-    return unless editable? user
+    return false unless editable? user
 
     return !system_default_was if dashboard_type != DashboardContentProject::TYPE_NAME