From e9cf1020de206607c679ca8bdfd1414a2446fbb4 Mon Sep 17 00:00:00 2001
From: Grzegorz Bizon <grzesiek.bizon@gmail.com>
Date: Fri, 11 May 2018 13:28:26 +0200
Subject: [PATCH 1/3] Improve fast specs helper to autoload the library

---
 spec/fast_spec_helper.rb | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/spec/fast_spec_helper.rb b/spec/fast_spec_helper.rb
index 978113a08a4..134eb25e4b1 100644
--- a/spec/fast_spec_helper.rb
+++ b/spec/fast_spec_helper.rb
@@ -3,14 +3,8 @@ require 'bundler/setup'
 ENV['GITLAB_ENV'] = 'test'
 ENV['IN_MEMORY_APPLICATION_SETTINGS'] = 'true'
 
-unless Object.respond_to?(:require_dependency)
-  class Object
-    alias_method :require_dependency, :require
-  end
-end
-
-# Defines Settings and Gitlab.config which are at the center of the app
 require_relative '../config/settings'
-require_relative '../lib/gitlab' unless defined?(Gitlab.config)
-
 require_relative 'support/rspec'
+require 'active_support/all'
+
+ActiveSupport::Dependencies.autoload_paths << 'lib'

From d134c0fb70eb9330680872edefa8841641931018 Mon Sep 17 00:00:00 2001
From: Grzegorz Bizon <grzesiek.bizon@gmail.com>
Date: Tue, 15 May 2018 10:38:00 +0200
Subject: [PATCH 2/3] Update docs describing `fast_spec_helper` best practices

---
 .../testing_guide/best_practices.md           | 27 ++++++++++++++++---
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/doc/development/testing_guide/best_practices.md b/doc/development/testing_guide/best_practices.md
index 61fa5459b91..5aa2068b495 100644
--- a/doc/development/testing_guide/best_practices.md
+++ b/doc/development/testing_guide/best_practices.md
@@ -134,11 +134,30 @@ really fast since:
 - gitlab-shell and Gitaly setup are skipped
 - Test repositories setup are skipped
 
-Note that in some cases, you might have to add some `require_dependency 'foo'`
-in your file under test since Rails autoloading is not available in these cases.
+`fast_spec_helper` also support autoloading classes that are located inside the
+`lib/` directory. It means that as long as your class / module is using only
+code from the `lib/` directory you will not need to explicitly load any
+dependencies. `fast_spec_helper` also loads all ActiveSupport extensions,
+including core extensions that are commonly used in the Rails environment.
 
-This shouldn't be a problem since explicitely listing dependencies should be
-considered a good practice anyway.
+Note that in some cases, you might still have to load some dependencies using
+`require_dependency` in your `*_spec.rb` file, like when a code is using gems.
+
+For example, if you want to test your code that is calling the
+`Gitlab::UntrustedRegexp` class, which under the hood uses `re2` library, you
+should be able to define a test using follow code snippet.
+
+```ruby
+require 'fast_spec_helper'
+require_dependency 're2'
+
+describe Gitlab::MyModule::MyClass do
+  # ...
+end
+```
+
+It takes around one second to load tests that are using `fast_spec_helper`
+instead of 30+ seconds in case of a regular `spec_helper`.
 
 ### `let` variables
 

From 7186f0de657f510e27e24b6845f99ded158118af Mon Sep 17 00:00:00 2001
From: Grzegorz Bizon <grzesiek.bizon@gmail.com>
Date: Tue, 15 May 2018 13:34:49 +0200
Subject: [PATCH 3/3] Improve testing best practices guidelines

It mentions that explicitly defining dependencies in sources is
preferred over defining such dependencies only in spec files.
---
 doc/development/testing_guide/best_practices.md | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/doc/development/testing_guide/best_practices.md b/doc/development/testing_guide/best_practices.md
index 5aa2068b495..c4d350e3676 100644
--- a/doc/development/testing_guide/best_practices.md
+++ b/doc/development/testing_guide/best_practices.md
@@ -141,20 +141,14 @@ dependencies. `fast_spec_helper` also loads all ActiveSupport extensions,
 including core extensions that are commonly used in the Rails environment.
 
 Note that in some cases, you might still have to load some dependencies using
-`require_dependency` in your `*_spec.rb` file, like when a code is using gems.
+`require_dependency` when a code is using gems or a dependency is not located
+in `lib/`.
 
 For example, if you want to test your code that is calling the
 `Gitlab::UntrustedRegexp` class, which under the hood uses `re2` library, you
-should be able to define a test using follow code snippet.
-
-```ruby
-require 'fast_spec_helper'
-require_dependency 're2'
-
-describe Gitlab::MyModule::MyClass do
-  # ...
-end
-```
+should either add `require_dependency 're2'` to files in your library that
+need `re2` gem, to make this requirement explicit, or you can add it to the
+spec itself, but the former is preferred.
 
 It takes around one second to load tests that are using `fast_spec_helper`
 instead of 30+ seconds in case of a regular `spec_helper`.