1 files changed, 37 insertions, 1 deletions
diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb
index 9cca103a18..ead42d64ec 100644
--- a/activerecord/lib/active_record/railtie.rb
+++ b/activerecord/lib/active_record/railtie.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require "active_record"
 require "rails"
 require "active_model/railtie"
@@ -26,6 +28,9 @@ module ActiveRecord
     config.active_record.use_schema_cache_dump = true
     config.active_record.maintain_test_schema = true
 
+    config.active_record.sqlite3 = ActiveSupport::OrderedOptions.new
+    config.active_record.sqlite3.represent_boolean_as_integer = nil
+
     config.eager_load_namespaces << ActiveRecord
 
     rake_tasks do
@@ -108,7 +113,9 @@ module ActiveRecord
 
     initializer "active_record.set_configs" do |app|
       ActiveSupport.on_load(:active_record) do
-        app.config.active_record.each do |k, v|
+        configs = app.config.active_record.dup
+        configs.delete(:sqlite3)
+        configs.each do |k, v|
           send "#{k}=", v
         end
       end
@@ -174,5 +181,34 @@ end_warning
         end
       end
     end
+
+    initializer "active_record.check_represent_sqlite3_boolean_as_integer" do
+      config.after_initialize do
+        ActiveSupport.on_load(:active_record_sqlite3adapter) do
+          represent_boolean_as_integer = Rails.application.config.active_record.sqlite3.delete(:represent_boolean_as_integer)
+          unless represent_boolean_as_integer.nil?
+            ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer = represent_boolean_as_integer
+          end
+
+          unless ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer
+            ActiveSupport::Deprecation.warn <<-MSG
+Leaving `ActiveRecord::ConnectionAdapters::SQLite3Adapter.represent_boolean_as_integer`
+set to false is deprecated. SQLite databases have used 't' and 'f' to serialize
+boolean values and must have old data converted to 1 and 0 (its native boolean
+serialization) before setting this flag to true. Conversion can be accomplished
+by setting up a rake task which runs
+
+  ExampleModel.where("boolean_column = 't'").update_all(boolean_column: 1)
+  ExampleModel.where("boolean_column = 'f'").update_all(boolean_column: 0)
+
+for all models and all boolean columns, after which the flag must be set to
+true by adding the following to your application.rb file:
+
+  Rails.application.config.active_record.sqlite3.represent_boolean_as_integer = true
+MSG
+          end
+        end
+      end
+    end
   end
 end