style(rubocop): Naming/MemoizedInstanceVariableName

app/jobs/unqueue_message_job.rb

@@ -455,6 +455,7 @@ class UnqueueMessageJob < Postal::Job
 
   private
 
+  # rubocop:disable Naming/MemoizedInstanceVariableName
   def cached_sender(klass, *args)
     @sender ||= begin
       sender = klass.new(*args)
@@ -462,5 +463,6 @@ class UnqueueMessageJob < Postal::Job
       sender
     end
   end
+  # rubocop:enable Naming/MemoizedInstanceVariableName
 
 end

app/models/incoming_message_prototype.rb

@@ -24,11 +24,11 @@ class IncomingMessagePrototype
   end
 
   def route
-    @routes ||= if @to.present?
-                  uname, domain = @to.split("@", 2)
-                  uname, _tag = uname.split("+", 2)
-                  @server.routes.includes(:domain).where(domains: { name: domain }, name: uname).first
-                end
+    @route ||= if @to.present?
+                 uname, domain = @to.split("@", 2)
+                 uname, _tag = uname.split("+", 2)
+                 @server.routes.includes(:domain).where(domains: { name: domain }, name: uname).first
+               end
   end
 
   def attachments

app/models/outgoing_message_prototype.rb

@@ -49,13 +49,11 @@ class OutgoingMessagePrototype
   end
 
   def find_domain
-    @domain ||= begin
-      domain = @server.authenticated_domain_for_address(@from)
-      if @server.allow_sender? && domain.nil?
-        domain = @server.authenticated_domain_for_address(@sender)
-      end
-      domain || :none
+    domain = @server.authenticated_domain_for_address(@from)
+    if @server.allow_sender? && domain.nil?
+      domain = @server.authenticated_domain_for_address(@sender)
     end
+    domain || :none
   end
 
   def to_addresses