Replace Hash#keys.each with Hash#each_key for some perf boost

app/controllers/posts_controller.rb

@@ -436,7 +436,7 @@ class PostsController < ApplicationController
       result[:is_warning] = false
     end
 
-    PostRevisor.tracked_topic_fields.keys.each do |f|
+    PostRevisor.tracked_topic_fields.each_key do |f|
       params.permit(f => [])
       result[f] = params[f] if params.has_key?(f)
     end

app/controllers/topics_controller.rb

@@ -128,7 +128,7 @@ class TopicsController < ApplicationController
     guardian.ensure_can_edit!(topic)
 
     changes = {}
-    PostRevisor.tracked_topic_fields.keys.each do |f|
+    PostRevisor.tracked_topic_fields.each_key do |f|
       changes[f] = params[f] if params.has_key?(f)
     end
 

app/models/directory_item.rb

@@ -19,7 +19,7 @@ class DirectoryItem < ActiveRecord::Base
   def self.refresh!
     ActiveRecord::Base.transaction do
       exec_sql "TRUNCATE TABLE directory_items"
-      period_types.keys.each {|p| refresh_period!(p)}
+      period_types.each_key {|p| refresh_period!(p)}
     end
   end
 

app/models/group.rb

@@ -151,7 +151,7 @@ class Group < ActiveRecord::Base
   end
 
   def self.ensure_automatic_groups!
-    AUTO_GROUPS.keys.each do |name|
+    AUTO_GROUPS.each_key do |name|
       refresh_automatic_group!(name) unless lookup_group(name)
     end
   end

app/models/incoming_links_report.rb

@@ -36,7 +36,7 @@ class IncomingLinksReport
     num_clicks  = link_count_per_user
     num_topics = topic_count_per_user
     report.data = []
-    num_clicks.keys.each do |username|
+    num_clicks.each_key do |username|
       report.data << {username: username, num_clicks: num_clicks[username], num_topics: num_topics[username]}
     end
     report.data = report.data.sort_by {|x| x[:num_clicks]}.reverse[0,10]
@@ -67,7 +67,7 @@ class IncomingLinksReport
     num_clicks  = link_count_per_domain
     num_topics = topic_count_per_domain(num_clicks.keys)
     report.data = []
-    num_clicks.keys.each do |domain|
+    num_clicks.each_key do |domain|
       report.data << {domain: domain, num_clicks: num_clicks[domain], num_topics: num_topics[domain]}
     end
     report.data = report.data.sort_by {|x| x[:num_clicks]}.reverse[0,10]

app/models/post.rb

@@ -221,7 +221,7 @@ class Post < ActiveRecord::Base
 
     TopicLink.where(domain: hosts.keys, user_id: acting_user.id)
              .group(:domain, :post_id)
-             .count.keys.each do |tuple|
+             .count.each_key do |tuple|
       domain = tuple[0]
       hosts[domain] = (hosts[domain] || 0) + 1
     end

app/models/topic.rb

@@ -613,7 +613,7 @@ class Topic < ActiveRecord::Base
   end
 
   def update_action_counts
-    PostActionType.types.keys.each do |type|
+    PostActionType.types.each_key do |type|
       count_field = "#{type}_count"
       update_column(count_field, Post.where(topic_id: id).sum(count_field))
     end

app/serializers/post_revision_serializer.rb

@@ -178,7 +178,7 @@ class PostRevisionSerializer < ApplicationSerializer
       }
 
       # Retrieve any `tracked_topic_fields`
-      PostRevisor.tracked_topic_fields.keys.each do |field|
+      PostRevisor.tracked_topic_fields.each_key do |field|
         if topic.respond_to?(field)
           latest_modifications[field.to_s] = [topic.send(field)]
         end
@@ -198,7 +198,7 @@ class PostRevisionSerializer < ApplicationSerializer
         revision[:revision] = pr.number
         revision[:hidden] = pr.hidden
 
-        pr.modifications.keys.each do |field|
+        pr.modifications.each_key do |field|
           revision[field] = pr.modifications[field][0]
         end
 
@@ -210,7 +210,7 @@ class PostRevisionSerializer < ApplicationSerializer
         cur = @all_revisions[r]
         prev = @all_revisions[r - 1]
 
-        cur.keys.each do |field|
+        cur.each_key do |field|
           prev[field] = prev.has_key?(field) ? prev[field] : cur[field]
         end
       end

lib/post_revisor.rb

@@ -300,7 +300,7 @@ class PostRevisor
     return unless revision = PostRevision.find_by(post_id: @post.id, number: @post.version)
     revision.user_id = @post.last_editor_id
     modifications = post_changes.merge(@topic_changes.diff)
-    modifications.keys.each do |field|
+    modifications.each_key do |field|
       if revision.modifications.has_key?(field)
         old_value = revision.modifications[field][0]
         new_value = modifications[field][1]

lib/score_calculator.rb

@@ -33,7 +33,7 @@ class ScoreCalculator
 
   def update_posts_score(min_topic_age)
     components = []
-    @weightings.keys.each { |k| components << "COALESCE(#{k}, 0) * :#{k}" }
+    @weightings.each_key { |k| components << "COALESCE(#{k}, 0) * :#{k}" }
     components = components.join(" + ")
 
     builder = SqlBuilder.new(

lib/site_settings/yaml_loader.rb

@@ -16,7 +16,7 @@ class SiteSettings::YamlLoader
 
   def load
     yaml = YAML.load_file(@file)
-    yaml.keys.each do |category|
+    yaml.each_key do |category|
       yaml[category].each do |setting_name, hash|
         if hash.is_a?(Hash)
           # Get default value for the site setting:

spec/integrity/i18n_spec.rb

@@ -16,7 +16,7 @@ describe "i18n integrity checks" do
   end
 
   it "needs an i18n key (notification_types) for each Notification type" do
-    Notification.types.keys.each do |type|
+    Notification.types.each_key do |type|
       I18n.t("notification_types.#{type}").should_not =~ /translation missing/
     end
   end