Fix seeding an empty database

app/models/user.rb

@@ -63,7 +63,7 @@ class User < ApplicationRecord
   end
 
   def cleanup_languages
-    self.languages_from = self.languages_from.gsub(/\s+/, '').downcase
-    self.languages_to = self.languages_to.gsub(/\s+/, '').downcase
+    self.languages_from = self.languages_from&.gsub(/\s+/, '')&.downcase
+    self.languages_to = self.languages_to&.gsub(/\s+/, '')&.downcase
   end
 end

db/seeds.rb

@@ -46,7 +46,7 @@ Conference.find_or_create_by!(slug: "37c3") do |c|
   c.location = "Congress Center Hamburg"
 end
 
-Conference.find_or_create_by!(slug: "38c3").tap do |c|
+Conference.find_or_create_by!(slug: "38c3") do |c|
   c.name = "38th Chaos Communication Congress (de-en)"
   c.time_zone = "Berlin"
   c.starts_at = DateTime.parse("27 December 2024 10:30 CET")
@@ -59,7 +59,7 @@ Conference.find_or_create_by!(slug: "38c3").tap do |c|
   c.save!
 end
 
-Conference.find_or_create_by!(slug: "38c3-more").tap do |c|
+Conference.find_or_create_by!(slug: "38c3-more") do |c|
   c.name = "38th Chaos Communication Congress (more languages)"
   c.time_zone = "Berlin"
   c.starts_at = DateTime.parse("27 December 2024 10:30 CET")
@@ -74,7 +74,7 @@ end
 
 if Rails.env.development?
   %w[coverage fog comedy adjust forge fail vigorous promise chemistry conception meat storage certain warm develop civilian cousin injection hammer health appetite conventional good snake grant suspect atmosphere linen wrong deal calf sea management silence watch nuance loan quit convert failure bracket slice sweat treaty plot still chimpanzee assume functional marsh dream mail state dorm kid formation secular agile beach guide salesperson merit goalkeeper incongruous cart pig joystick regulation apparatus myth patent glue behead flu departure spectrum parking indication delay hesitate viable lay treat cooperative sensation auction sphere stain tap pass].each do |username|
-    User.find_or_create_by(name: username).tap do |u|
+    User.find_or_create_by(name: username) do |u|
       u.email = "c3lingo+#{username}@x.moeffju.net"
       u.invitation_token = "gargamel"
       u.save!