Log call site for all queries

This new ActiveRecord configuration option allows you to easily
pinpoint what line of application code is triggering SQL queries in the
development log by appending below each SQL statement log the line of
Ruby code that triggered it.

It’s useful with N+1 issues, and to locate stray queries.

By default this new option ignores Rails and Ruby code in order to
surface only callers from your application Ruby code or your gems.

It is enabled on newly generated Rails 5.2 applications and can be
enabled on existing Rails applications:

```ruby
Rails.application.configure do
  # ...
  config.active_record.verbose_query_logs = true
end
```

The `rails app:upgrade` task will also add it to
`config/development.rb`.

This feature purposely avoids coupling with
ActiveSupport::BacktraceCleaner since ActiveRecord can be used without
ActiveRecord. This decision can be reverted in the future to allow more
configurable backtraces (the exclusion of gem callers for example).

2 files changed, 11 insertions, 4 deletions

diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index edb6190ed0..d28f7ffc7f 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -1317,7 +1317,7 @@ module ApplicationTests
       assert_equal 200, last_response.status
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is :log by default on development" do
+    test "config.action_controller.action_on_unpermitted_parameters is :log by default in development" do
       app "development"
 
       force_lazy_load_hooks { ActionController::Base }
@@ -1326,7 +1326,7 @@ module ApplicationTests
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is :log by default on test" do
+    test "config.action_controller.action_on_unpermitted_parameters is :log by default in test" do
       app "test"
 
       force_lazy_load_hooks { ActionController::Base }
@@ -1335,7 +1335,7 @@ module ApplicationTests
       assert_equal :log, ActionController::Parameters.action_on_unpermitted_parameters
     end
 
-    test "config.action_controller.action_on_unpermitted_parameters is false by default on production" do
+    test "config.action_controller.action_on_unpermitted_parameters is false by default in production" do
       app "production"
 
       force_lazy_load_hooks { ActionController::Base }
@@ -1482,12 +1482,18 @@ module ApplicationTests
       assert_not ActiveRecord::Base.dump_schema_after_migration
     end
 
-    test "config.active_record.dump_schema_after_migration is true by default on development" do
+    test "config.active_record.dump_schema_after_migration is true by default in development" do
       app "development"
 
       assert ActiveRecord::Base.dump_schema_after_migration
     end
 
+    test "config.active_record.verbose_query_logs is false by default in development" do
+      app "development"
+
+      assert_not ActiveRecord::Base.verbose_query_logs
+    end
+
     test "config.annotations wrapping SourceAnnotationExtractor::Annotation class" do
       make_basic_app do |application|
         application.config.annotations.register_extensions("coffee") do |tag|
diff --git a/railties/test/application/initializers/notifications_test.rb b/railties/test/application/initializers/notifications_test.rb
index 23b20d578c..c65c955734 100644
--- a/railties/test/application/initializers/notifications_test.rb
+++ b/railties/test/application/initializers/notifications_test.rb
@@ -32,6 +32,7 @@ module ApplicationTests
 
       logger = ActiveSupport::LogSubscriber::TestHelper::MockLogger.new
       ActiveRecord::Base.logger = logger
+      ActiveRecord::Base.verbose_query_logs = false
 
       # Mimic Active Record notifications
       instrument "sql.active_record", name: "SQL", sql: "SHOW tables"