Move GraphQL docs renderer to tooling

This removes the early return that we have on these classes to prevent
eager loading in production.

This also prepares us for the switch to Zeitwerk because it complains
that the file does not define a class in production.

lib/tasks/gitlab/graphql.rake

@@ -3,11 +3,12 @@
 return if Rails.env.production?
 
 require 'graphql/rake_task'
+require_relative '../../../tooling/graphql/docs/renderer'
 
 namespace :gitlab do
   OUTPUT_DIR = Rails.root.join("doc/api/graphql/reference")
   TEMP_SCHEMA_DIR = Rails.root.join('tmp/tests/graphql')
-  TEMPLATES_DIR = 'lib/gitlab/graphql/docs/templates/'
+  TEMPLATES_DIR = 'tooling/graphql/docs/templates/'
 
   # Make all feature flags enabled so that all feature flag
   # controlled fields are considered visible and are output.
@@ -110,7 +111,7 @@ namespace :gitlab do
 
     desc 'GitLab | GraphQL | Generate GraphQL docs'
     task compile_docs: [:environment, :enable_feature_flags] do
-      renderer = Gitlab::Graphql::Docs::Renderer.new(GitlabSchema, render_options)
+      renderer = Tooling::Graphql::Docs::Renderer.new(GitlabSchema, render_options)
 
       renderer.write
 
@@ -119,7 +120,7 @@ namespace :gitlab do
 
     desc 'GitLab | GraphQL | Check if GraphQL docs are up to date'
     task check_docs: [:environment, :enable_feature_flags] do
-      renderer = Gitlab::Graphql::Docs::Renderer.new(GitlabSchema, render_options)
+      renderer = Tooling::Graphql::Docs::Renderer.new(GitlabSchema, render_options)
 
       doc = File.read(Rails.root.join(OUTPUT_DIR, 'index.md'))
 

spec/lib/gitlab/graphql/docs/renderer_spec.rb → spec/tooling/graphql/docs/renderer_spec.rb

 # frozen_string_literal: true
 
-require 'spec_helper'
+require_relative '../../../../tooling/graphql/docs/renderer'
 
-RSpec.describe Gitlab::Graphql::Docs::Renderer do
+RSpec.describe Tooling::Graphql::Docs::Renderer do
   describe '#contents' do
     shared_examples 'renders correctly as GraphQL documentation' do
       it 'contains the expected section' do
@@ -12,7 +12,7 @@ RSpec.describe Gitlab::Graphql::Docs::Renderer do
       end
     end
 
-    let(:template) { Rails.root.join('lib/gitlab/graphql/docs/templates/default.md.haml') }
+    let(:template) { Rails.root.join('tooling/graphql/docs/templates/default.md.haml') }
     let(:field_description) { 'List of objects.' }
     let(:type) { ::GraphQL::INT_TYPE }
 

lib/gitlab/graphql/docs/helper.rb → tooling/graphql/docs/helper.rb

 # frozen_string_literal: true
 
-return if Rails.env.production?
+require 'gitlab/utils/strong_memoize'
 
-module Gitlab
+module Tooling
   module Graphql
     module Docs
       # We assume a few things about the schema. We use the graphql-ruby gem, which enforces:

lib/gitlab/graphql/docs/renderer.rb → tooling/graphql/docs/renderer.rb

 # frozen_string_literal: true
 
-return if Rails.env.production?
+require_relative 'helper'
 
-module Gitlab
+module Tooling
   module Graphql
     module Docs
       # Gitlab renderer for graphql-docs.
@@ -14,7 +14,7 @@ module Gitlab
       #   output_dir: The folder where the markdown files will be saved
       #   template: The path of the haml template to be parsed
       class Renderer
-        include Gitlab::Graphql::Docs::Helper
+        include Tooling::Graphql::Docs::Helper
 
         attr_reader :schema