Merge branch 'rubocop/enable-access-modifiers-cops' into 'master'

Enable Rubocop cops that check access modifiers

## What does this MR do?

This MR enables Rubocop cops that detect methods that should be restricted but are the part of public API because of access modifiers used improperly.

This also fixes existing offenses.

## Why was this MR needed?

Some method in our codebase are public instead of being private because it is sometimes difficult to get it right without static analysis.

## What are the relevant issue numbers?

See #17478  
Closes #17372 

See merge request !5014

3 files changed, 21 insertions, 19 deletions

diff --git a/lib/banzai/filter/emoji_filter.rb b/lib/banzai/filter/emoji_filter.rb
index ae7d31cf191..2492b5213ac 100644
--- a/lib/banzai/filter/emoji_filter.rb
+++ b/lib/banzai/filter/emoji_filter.rb
@@ -38,6 +38,11 @@ module Banzai
         end
       end
 
+      # Build a regexp that matches all valid :emoji: names.
+      def self.emoji_pattern
+        @emoji_pattern ||= /:(#{Gitlab::Emoji.emojis_names.map { |name| Regexp.escape(name) }.join('|')}):/
+      end
+
       private
 
       def emoji_url(name)
@@ -59,11 +64,6 @@ module Banzai
         ActionController::Base.helpers.url_to_image(image)
       end
 
-      # Build a regexp that matches all valid :emoji: names.
-      def self.emoji_pattern
-        @emoji_pattern ||= /:(#{Gitlab::Emoji.emojis_names.map { |name| Regexp.escape(name) }.join('|')}):/
-      end
-
       def emoji_pattern
         self.class.emoji_pattern
       end
diff --git a/lib/banzai/filter/markdown_filter.rb b/lib/banzai/filter/markdown_filter.rb
index 9b209533a89..ff580ec68f8 100644
--- a/lib/banzai/filter/markdown_filter.rb
+++ b/lib/banzai/filter/markdown_filter.rb
@@ -12,7 +12,12 @@ module Banzai
         html
       end
 
-      private
+      def self.renderer
+        @renderer ||= begin
+          renderer = Redcarpet::Render::HTML.new
+          Redcarpet::Markdown.new(renderer, redcarpet_options)
+        end
+      end
 
       def self.redcarpet_options
         # https://github.com/vmg/redcarpet#and-its-like-really-simple-to-use
@@ -28,12 +33,7 @@ module Banzai
         }.freeze
       end
 
-      def self.renderer
-        @renderer ||= begin
-          renderer = Redcarpet::Render::HTML.new
-          Redcarpet::Markdown.new(renderer, redcarpet_options)
-        end
-      end
+      private_class_method :redcarpet_options
     end
   end
 end
diff --git a/lib/banzai/renderer.rb b/lib/banzai/renderer.rb
index 910687a7b6a..a4ae27eefd8 100644
--- a/lib/banzai/renderer.rb
+++ b/lib/banzai/renderer.rb
@@ -1,5 +1,7 @@
 module Banzai
   module Renderer
+    extend self
+
     # Convert a Markdown String into an HTML-safe String of HTML
     #
     # Note that while the returned HTML will have been sanitized of dangerous
@@ -14,7 +16,7 @@ module Banzai
     # context  - Hash of context options passed to our HTML Pipeline
     #
     # Returns an HTML-safe String
-    def self.render(text, context = {})
+    def render(text, context = {})
       cache_key = context.delete(:cache_key)
       cache_key = full_cache_key(cache_key, context[:pipeline])
 
@@ -52,7 +54,7 @@ module Banzai
     #    texts_and_contexts
     #    => [{ text: '### Hello',
     #          context: { cache_key: [note, :note] } }]
-    def self.cache_collection_render(texts_and_contexts)
+    def cache_collection_render(texts_and_contexts)
       items_collection = texts_and_contexts.each_with_index do |item, index|
         context = item[:context]
         cache_key = full_cache_multi_key(context.delete(:cache_key), context[:pipeline])
@@ -81,7 +83,7 @@ module Banzai
       items_collection.map { |item| item[:rendered] }
     end
 
-    def self.render_result(text, context = {})
+    def render_result(text, context = {})
       text = Pipeline[:pre_process].to_html(text, context) if text
 
       Pipeline[context[:pipeline]].call(text, context)
@@ -100,7 +102,7 @@ module Banzai
     #            :user      - User object
     #
     # Returns an HTML-safe String
-    def self.post_process(html, context)
+    def post_process(html, context)
       context = Pipeline[context[:pipeline]].transform_context(context)
 
       pipeline = Pipeline[:post_process]
@@ -113,7 +115,7 @@ module Banzai
 
     private
 
-    def self.cacheless_render(text, context = {})
+    def cacheless_render(text, context = {})
       Gitlab::Metrics.measure(:banzai_cacheless_render) do
         result = render_result(text, context)
 
@@ -126,7 +128,7 @@ module Banzai
       end
     end
 
-    def self.full_cache_key(cache_key, pipeline_name)
+    def full_cache_key(cache_key, pipeline_name)
       return unless cache_key
       ["banzai", *cache_key, pipeline_name || :full]
     end
@@ -134,7 +136,7 @@ module Banzai
     # To map Rails.cache.read_multi results we need to know the Rails.cache.expanded_key.
     # Other option will be to generate stringified keys on our side and don't delegate to Rails.cache.expanded_key
     # method.
-    def self.full_cache_multi_key(cache_key, pipeline_name)
+    def full_cache_multi_key(cache_key, pipeline_name)
       return unless cache_key
       Rails.cache.send(:expanded_key, full_cache_key(cache_key, pipeline_name))
     end