Merge branch 'use-rules-in-rails' into 'master'

Use 'rules' in '.gitlab/ci/rails.gitlab-ci.yml' and '.gitlab/ci/dev-fixtures.gitlab-ci.yml'

See merge request gitlab-org/gitlab!24492

.gitlab/ci/dev-fixtures.gitlab-ci.yml

+# Make sure to update all the similar conditions in other CI config files if you modify these conditions
+.if-not-ee: &if-not-ee
+  if: '$CI_PROJECT_NAME !~ /^gitlab(-ee)?$/'
+
+# Make sure to update all the similar conditions in other CI config files if you modify these conditions
+.if-default-refs: &if-default-refs
+  if: '$CI_COMMIT_REF_NAME == "master" || $CI_COMMIT_REF_NAME =~ /^[\d-]+-stable(-ee)?$/ || $CI_COMMIT_REF_NAME =~ /^\d+-\d+-auto-deploy-\d+$/ || $CI_COMMIT_REF_NAME =~ /^security\// || $CI_MERGE_REQUEST_IID || $CI_COMMIT_TAG'
+
+# Make sure to update all the similar patterns in other CI config files if you modify these patterns
+.code-backstage-patterns: &code-backstage-patterns
+  - ".gitlab/ci/**/*"
+  - ".{eslintignore,gitattributes,nvmrc,prettierrc,stylelintrc,yamllint}"
+  - ".{codeclimate,eslintrc,gitlab-ci,haml-lint,haml-lint_todo,rubocop,rubocop_todo,scss-lint}.yml"
+  - ".csscomb.json"
+  - "Dockerfile.assets"
+  - "*_VERSION"
+  - "Gemfile{,.lock}"
+  - "Rakefile"
+  - "{babel.config,jest.config}.js"
+  - "config.ru"
+  - "{package.json,yarn.lock}"
+  - "{,ee/}{app,bin,config,db,haml_lint,lib,locale,public,scripts,symbol,vendor}/**/*"
+  - "doc/api/graphql/reference/*" # Files in this folder are auto-generated
+  # Backstage changes
+  - "Dangerfile"
+  - "danger/**/*"
+  - "{,ee/}fixtures/**/*"
+  - "{,ee/}rubocop/**/*"
+  - "{,ee/}spec/**/*"
+  - "doc/README.md"  # Some RSpec test rely on this file
+
+.dev-fixtures:rules:ee-and-foss:
+  rules:
+    - <<: *if-default-refs
+      changes: *code-backstage-patterns
+      when: on_success
+
+.dev-fixtures:rules:ee-only:
+  rules:
+    - <<: *if-not-ee
+      when: never
+    - <<: *if-default-refs
+      changes: *code-backstage-patterns
+      when: on_success
+
 .run-dev-fixtures:
   extends:
-    - .only-code-rails-job-base
+    - .default-tags
+    - .default-retry
+    - .default-cache
+    - .default-before_script
     - .use-pg9
   stage: test
   needs: ["setup-test-env"]
@@ -13,17 +61,19 @@
     SIZE: 0 # number of external projects to fork, requires network connection
     # SEED_NESTED_GROUPS: "false" # requires network connection
 
-run-dev-fixtures-foss:
-  extends: .run-dev-fixtures
+run-dev-fixtures:
+  extends:
+    - .run-dev-fixtures
+    - .dev-fixtures:rules:ee-and-foss
   script:
     - scripts/gitaly-test-spawn
     - RAILS_ENV=test bundle exec rake db:seed_fu
 
 run-dev-fixtures-ee:
   extends:
-    - .only-ee
-    - .use-pg9-ee
     - .run-dev-fixtures
+    - .dev-fixtures:rules:ee-only
+    - .use-pg9-ee
   script:
     - scripts/gitaly-test-spawn
     - cp ee/db/fixtures/development/* $FIXTURE_PATH