address PR feedback + finish old_short_code change

- magic of Rails means that the table names do NOT need to be specified
- belongs_to is smart about foreign key names

- missing definition of old_short_code missing from locations before use

app/models/backup_library.rb

@@ -1,3 +1,2 @@
 class BackupLibrary < ActiveRecord::Base
-  self.table_name = 'backup_libraries'
 end

app/models/backup_location.rb

@@ -1,4 +1,3 @@
 class BackupLocation < ActiveRecord::Base
-  belongs_to :backup_library, foreign_key: :library_id
-  self.table_name = 'backup_locations'
+  belongs_to :backup_library
 end

db/migrate/20200128220027_change_location_short_code.rb

@@ -58,14 +58,17 @@ class ChangeLocationShortCode < ActiveRecord::Migration
   }
 
   def up
+    add_column :locations, :old_short_code, :string
     CODES.each do |old_code,new_code|
       entry = Location.find_or_initialize_by(short_code: old_code)
       entry.short_code = new_code
+      entry.old_short_code = old_code
       entry.save
     end
   end
 
   def down
+    remove_column :locations, :old_short_code
     CODES.invert.each do |old_code,new_code|
       entry = Location.find_or_initialize_by(short_code: old_code)
       entry.short_code = new_code

db/schema.rb

@@ -72,12 +72,13 @@
   end
 
   create_table "locations", force: :cascade do |t|
-    t.string   "short_code", limit: 255
-    t.string   "name",       limit: 255
-    t.string   "url",        limit: 255
-    t.integer  "library_id", limit: 4
-    t.datetime "created_at",             null: false
-    t.datetime "updated_at",             null: false
+    t.string   "short_code",     limit: 255
+    t.string   "name",           limit: 255
+    t.string   "url",            limit: 255
+    t.integer  "library_id",     limit: 4
+    t.datetime "created_at",                 null: false
+    t.datetime "updated_at",                 null: false
+    t.string   "old_short_code", limit: 255
   end
 
   add_index "locations", ["library_id"], name: "index_locations_on_library_id", using: :btree

lib/generators/symphony_nightly/templates/update_symphony_nightly.erb

@@ -89,6 +89,7 @@ class UpdateSymphonyNightly<%= Time.now.strftime('%Y%m%d') %> < ActiveRecord::Mi
     end
     create_table :backup_locations do |t|
       t.string :short_code
+      t.string :old_short_code
       t.string :name
       t.string :url
       t.references :backup_library, index: true, foreign_key: true
@@ -139,6 +140,7 @@ class UpdateSymphonyNightly<%= Time.now.strftime('%Y%m%d') %> < ActiveRecord::Mi
   def create_table_locations
     create_table :locations do |t|
       t.string :short_code
+      t.string :old_short_code
       t.string :name
       t.string :url
       t.references :library, index: true, foreign_key: true