Merge branch 'do-not-eager_load-by-default-in-test-env' into 'master'

Do not `eager_load` by default in the test environment

See merge request gitlab-org/gitlab!72964

.gitlab/ci/rails.gitlab-ci.yml

@@ -168,7 +168,6 @@ setup-test-env:
     - .rails:rules:code-backstage-qa
   stage: prepare
   variables:
-    GITLAB_TEST_EAGER_LOAD: "0"
     SETUP_DB: "false"
   script:
     - run_timed_command "scripts/setup-test-env"

.gitpod.yml

@@ -69,15 +69,13 @@ tasks:
         printf "Waiting for GitLab at $(gp url 3000) ..."
         # Check /-/readiness which returns JSON, but we're only interested in the exit code
         #
-        # We use http://localhost:3000 instead of the public hostname because 
+        # We use http://localhost:3000 instead of the public hostname because
         # it's no longer possible to access as specific cookies are required
         until curl --silent --no-buffer --fail http://localhost:3000/-/readiness > /dev/null 2>&1; do printf '.'; sleep 5; done && echo ""
         # Give Gitpod a few more seconds to set up everything ...
         sleep 5
         printf "$(date) – GitLab is up (took ~%.1f minutes)\n" "$((10*$SECONDS/60))e-1" | tee -a /workspace/startup.log
         gp preview $(gp url 3000) || true
-        # Speed up backend tests
-        export GITLAB_TEST_EAGER_LOAD=false
       )
 
 ports:

config/environments/test.rb

@@ -49,7 +49,7 @@ Rails.application.configure do
   # Print deprecation notices to the stderr
   config.active_support.deprecation = :stderr
 
-  config.eager_load = Gitlab::Utils.to_boolean(ENV['GITLAB_TEST_EAGER_LOAD'], default: true)
+  config.eager_load = Gitlab::Utils.to_boolean(ENV['GITLAB_TEST_EAGER_LOAD'], default: ENV['CI'].present?)
 
   config.cache_store = :null_store
 

doc/development/testing_guide/best_practices.md

@@ -50,6 +50,20 @@ bundle exec guard
 
 When using spring and guard together, use `SPRING=1 bundle exec guard` instead to make use of spring.
 
+### Eager loading the application code
+
+By default, the application code:
+
+- Isn't eagerly loaded in the `test` environment.
+- Is eagerly loaded in CI/CD (when `ENV['CI'].present?`) to surface any potential loading issues.
+
+If you need to enable eager loading when executing tests,
+use the `GITLAB_TEST_EAGER_LOAD` environment variable:
+
+```shell
+GITLAB_TEST_EAGER_LOAD=1 bin/rspec spec/models/project_spec.rb
+```
+
 ### Ruby warnings
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/47767) in GitLab 13.7.