diff --git a/app/models/commit.rb b/app/models/commit.rb
index b406a4dd8d2..6bb018b086f 100644
--- a/app/models/commit.rb
+++ b/app/models/commit.rb
@@ -15,8 +15,8 @@ class Commit
   DIFF_SAFE_LINES = Gitlab::Git::DiffCollection::DEFAULT_LIMITS[:max_lines]
 
   # Commits above this size will not be rendered in HTML
-  DIFF_HARD_LIMIT_FILES = 1000 unless defined?(DIFF_HARD_LIMIT_FILES)
-  DIFF_HARD_LIMIT_LINES = 50000 unless defined?(DIFF_HARD_LIMIT_LINES)
+  DIFF_HARD_LIMIT_FILES = 1000
+  DIFF_HARD_LIMIT_LINES = 50000
 
   class << self
     def decorate(commits, project)
diff --git a/app/models/group.rb b/app/models/group.rb
index 9a04ac70d35..1f8432e3320 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -15,7 +15,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class Group < Namespace
   include Gitlab::ConfigHelper
diff --git a/app/models/issue.rb b/app/models/issue.rb
index 2f773869603..a009e235b37 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -20,7 +20,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class Issue < ActiveRecord::Base
   include InternalId
diff --git a/app/models/merge_request.rb b/app/models/merge_request.rb
index e410febdfff..47da154dd81 100644
--- a/app/models/merge_request.rb
+++ b/app/models/merge_request.rb
@@ -27,9 +27,6 @@
 #  merge_commit_sha          :string
 #
 
-require Rails.root.join("app/models/commit")
-require Rails.root.join("lib/static_model")
-
 class MergeRequest < ActiveRecord::Base
   include InternalId
   include Issuable
diff --git a/app/models/merge_request_diff.rb b/app/models/merge_request_diff.rb
index 33884118595..0580cafdd1b 100644
--- a/app/models/merge_request_diff.rb
+++ b/app/models/merge_request_diff.rb
@@ -11,8 +11,6 @@
 #  updated_at       :datetime
 #
 
-require Rails.root.join("app/models/commit")
-
 class MergeRequestDiff < ActiveRecord::Base
   include Sortable
 
diff --git a/app/models/note.rb b/app/models/note.rb
index 87ced65c650..71b4293d57a 100644
--- a/app/models/note.rb
+++ b/app/models/note.rb
@@ -20,7 +20,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class Note < ActiveRecord::Base
   include Gitlab::CurrentSettings
diff --git a/app/models/project.rb b/app/models/project.rb
index e7dac23a122..8f0272d2ce0 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -40,7 +40,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class Project < ActiveRecord::Base
   include Gitlab::ConfigHelper
diff --git a/app/models/project_import_data.rb b/app/models/project_import_data.rb
index 79efb403058..2c0ae312f1b 100644
--- a/app/models/project_import_data.rb
+++ b/app/models/project_import_data.rb
@@ -8,7 +8,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class ProjectImportData < ActiveRecord::Base
   belongs_to :project
diff --git a/app/models/user.rb b/app/models/user.rb
index 031315debd7..ab48f8f1960 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -63,7 +63,6 @@
 #
 
 require 'carrierwave/orm/activerecord'
-require 'file_size_validator'
 
 class User < ActiveRecord::Base
   extend Gitlab::ConfigHelper
diff --git a/lib/file_size_validator.rb b/lib/file_size_validator.rb
index 2eae55e534b..440dd44ece7 100644
--- a/lib/file_size_validator.rb
+++ b/lib/file_size_validator.rb
@@ -1,9 +1,9 @@
 class FileSizeValidator < ActiveModel::EachValidator
-  MESSAGES  = { is: :wrong_size, minimum: :size_too_small, maximum: :size_too_big }.freeze
-  CHECKS    = { is: :==, minimum: :>=, maximum: :<= }.freeze
+  MESSAGES = { is: :wrong_size, minimum: :size_too_small, maximum: :size_too_big }.freeze
+  CHECKS   = { is: :==, minimum: :>=, maximum: :<= }.freeze
 
-  DEFAULT_TOKENIZER = lambda { |value| value.split(//) }
-  RESERVED_OPTIONS  = [:minimum, :maximum, :within, :is, :tokenizer, :too_short, :too_long]
+  DEFAULT_TOKENIZER = -> (value) { value.split(//) }.freeze
+  RESERVED_OPTIONS  = [:minimum, :maximum, :within, :is, :tokenizer, :too_short, :too_long].freeze
 
   def initialize(options)
     if range = (options.delete(:in) || options.delete(:within))