VehicleJourney.lines: Change query to only get lines for route

Johan recommended using an `IN` query to only get the lines in the
current scope. I assumed I'd be covered by the schema and how only the
lines for the current referential are in the schema, but this is
probably a more reasonable way to get associated lines.

Refs #5576

1 files changed, 2 insertions, 1 deletions

diff --git a/app/models/chouette/vehicle_journey.rb b/app/models/chouette/vehicle_journey.rb
index 30b8903a1..6146d5be8 100644
--- a/app/models/chouette/vehicle_journey.rb
+++ b/app/models/chouette/vehicle_journey.rb
@@ -377,7 +377,8 @@ module Chouette
     end
 
     def self.lines
-      Chouette::Line.joins(routes: :vehicle_journeys).distinct
+      lines_query = joins(:route).select("routes.line_id").to_sql
+      Chouette::Line.where("id IN (#{lines_query})")
     end
   end
 end