Use rchardet instead of charlock_holmes gem

Gemfile

@@ -180,7 +180,7 @@ gem 'rqrcode'
 
 gem 'sshkey', require: false
 
-gem 'charlock_holmes', require: false
+gem 'rchardet', require: false
 
 if ENV["IMPORT"] == "1"
   gem 'mysql2'

Gemfile.lock

@@ -75,7 +75,6 @@ GEM
       uniform_notifier (~> 1.11.0)
     byebug (10.0.2)
     certified (1.0.0)
-    charlock_holmes (0.7.6)
     chunky_png (1.3.10)
     claide (1.0.2)
     claide-plugins (0.9.2)
@@ -321,6 +320,7 @@ GEM
       ffi (>= 1.0.6)
       msgpack (>= 0.4.3)
       trollop (>= 1.16.2)
+    rchardet (1.8.0)
     redis (4.0.1)
     redis-namespace (1.6.0)
       redis (>= 3.0.4)
@@ -457,7 +457,6 @@ DEPENDENCIES
   bullet
   byebug
   certified
-  charlock_holmes
   cppjieba_rb
   danger
   discourse_image_optim
@@ -523,6 +522,7 @@ DEPENDENCIES
   rb-fsevent
   rb-inotify (~> 0.9)
   rbtrace
+  rchardet
   redis
   redis-namespace
   rinku

app/jobs/scheduled/poll_feed.rb

@@ -90,7 +90,7 @@ module Jobs
       def parsed_feed
         raw_feed, encoding = fetch_rss
         encoded_feed = Encodings.try_utf8(raw_feed, encoding) if encoding
-        encoded_feed = Encodings.to_utf8(raw_feed, encoding_hint: encoding) unless encoded_feed
+        encoded_feed = Encodings.to_utf8(raw_feed) unless encoded_feed
 
         return nil if encoded_feed.blank?
 

lib/encodings.rb

@@ -1,20 +1,12 @@
-require 'charlock_holmes'
+require 'rchardet'
 
 module Encodings
-  BINARY_SCAN_LENGTH = 0
+  def self.to_utf8(string)
+    result = CharDet.detect(string)
 
-  def self.to_utf8(string, encoding_hint: nil, delete_bom: true)
-    detector = CharlockHolmes::EncodingDetector.new(BINARY_SCAN_LENGTH)
-    result = detector.detect(string, encoding_hint&.to_s)
-
-    if result && result[:encoding]
-      string = CharlockHolmes::Converter.convert(string, result[:encoding], Encoding::UTF_8.name)
-    else
-      string = string.encode(Encoding::UTF_8, undef: :replace, invalid: :replace, replace: '')
-    end
-
-    delete_bom!(string) if delete_bom
-    string
+    encoded_string = try_utf8(string, result['encoding']) if result && result['encoding']
+    encoded_string = force_utf8(string) if encoded_string.nil?
+    encoded_string
   end
 
   def self.try_utf8(string, source_encoding)
@@ -26,6 +18,14 @@ module Encodings
     nil
   end
 
+  def self.force_utf8(string)
+    encoded_string = string.encode(Encoding::UTF_8,
+                                   undef: :replace,
+                                   invalid: :replace,
+                                   replace: '')
+    delete_bom!(encoded_string)
+  end
+
   def self.delete_bom!(string)
     string.sub!(/\A\xEF\xBB\xBF/, '') unless string.blank?
     string

spec/lib/encodings_spec.rb

@@ -1,9 +1,9 @@
 require 'rails_helper'
 
 describe Encodings do
-  def to_utf8(filename, encoding_hint = nil)
+  def to_utf8(filename)
     string = File.read("#{Rails.root}/spec/fixtures/encodings/#{filename}").chomp
-    Encodings.to_utf8(string, encoding_hint: encoding_hint)
+    Encodings.to_utf8(string)
   end
 
   context "unicode" do