Refactor after code review

lib/tasks/user_username_change.rake

@@ -1,50 +1,42 @@
 namespace :cartodb do
   namespace :user do
-      desc 'Change user username'
-      task :change_username, [:old_username, :new_username] => :environment do |_task, args|
-        raise "You must pass an existing username, and a new username for the existing user" unless args[:old_username] && args[:new_username]
+    desc 'Change user username'
+    task :change_username, [:old_username, :new_username] => :environment do |_task, args|
+      raise "You must pass an existing username, and a new username for the existing user" unless args[:old_username] && args[:new_username]
 
-        user = User.find(username: args[:old_username])
-        raise "User with username #{args[:old_username]} doesn't exist!" unless user
+      user = User.find(username: args[:old_username])
+      raise "User with username #{args[:old_username]} doesn't exist!" unless user
 
-        # Update username and database_schema
-        user.username = args[:new_username]
-        user.database_schema = args[:new_username]
-        user.save
+      # Update username and database_schema
+      user.username = args[:new_username]
+      user.database_schema = args[:new_username]
+      user.save
 
-        # Update Redis metadata
-        user.save_metadata
+      # Update Redis metadata
+      user.save_metadata
 
-        # Rename user and database schema
-        user.in_database({as: :superuser}) do |db|
-          db.run("ALTER SCHEMA \"#{args[:old_username]}\" RENAME TO \"#{args[:new_username]}\";")
-        end
+      # Rename user and database schema
+      user.in_database(as: :superuser) { |db|
+        db.run("ALTER SCHEMA \"#{args[:old_username]}\" RENAME TO \"#{args[:new_username]}\";")
+      }
 
-        # Regenerate API Keys
-        user.carto_user.api_keys.each { |api_key|
-          if api_key.master?
-            api_key.regenerate_token!
-          end
-        }
+      # Regenerate API Keys
+      user.carto_user.api_keys.find(&:master?).try(:regenerate_token!)
 
-        # Fix map analysis
-        user.carto_user.tables.each do |table|
-          table.dependent_visualizations.each do |visualization|
-            visualization.analyses.each do |analysis|
-              analysis.update_table_name(
-                "#{args[:old_username]}.#{table.name}",
-                "\"#{args[:new_username]}\".#{table.name}"
-              )
-            end
+      # Fix map analysis
+      user.carto_user.tables.each do |table|
+        table.dependent_visualizations.each do |visualization|
+          visualization.analyses.each do |analysis|
+            analysis.update_table_name(
+              "#{args[:old_username]}.#{table.name}",
+              "\"#{args[:new_username]}\".#{table.name}"
+            )
           end
         end
-
-        # Fix public maps
-        Carto::Visualization.where(type: 'derived', user: user.carto_user).each { |visualization|
-          if visualization.published?
-            visualization.create_mapcap!
-          end
-        }
       end
+
+      # Fix public maps
+      Carto::Visualization.where(type: 'derived', user: user.carto_user).select(&:published?).each { |visualization| visualization.create_mapcap! }
+    end
   end
 end