Replace WhatLanguage with CLD

Gemfile

@@ -57,7 +57,6 @@ gem 'statsd-instrument'
 gem 'twitter-text'
 gem 'tzinfo-data'
 gem 'webpacker', '~>1.2'
-gem 'whatlanguage'
 
 # For some reason the view specs start failing without this
 gem 'react-rails'

Gemfile.lock

@@ -466,7 +466,6 @@ GEM
     websocket-driver (0.6.5)
       websocket-extensions (>= 0.1.0)
     websocket-extensions (0.1.2)
-    whatlanguage (1.0.6)
     xpath (2.0.0)
       nokogiri (~> 1.3)
 
@@ -553,7 +552,6 @@ DEPENDENCIES
   uglifier (>= 1.3.0)
   webmock
   webpacker (~> 1.2)
-  whatlanguage
 
 RUBY VERSION
    ruby 2.4.1p111

app/lib/language_detector.rb

@@ -9,11 +9,23 @@ def initialize(text, account = nil)
   end
 
   def to_iso_s
-    WhatLanguage.new(:all).language_iso(text_without_urls) || default_locale.to_sym
+    detected_language_code || default_locale.to_sym
   end
 
   private
 
+  def detected_language_code
+    detected_language[:code].to_sym if detected_language_reliable?
+  end
+
+  def detected_language
+    @_detected_language ||= CLD.detect_language(text_without_urls)
+  end
+
+  def detected_language_reliable?
+    detected_language[:reliable]
+  end
+
   def text_without_urls
     text.dup.tap do |new_text|
       URI.extract(new_text).each do |url|

spec/lib/language_detector_spec.rb

@@ -25,15 +25,15 @@
 
     describe 'when language can\'t be detected' do
       it 'confirm language engine cant detect' do
-        result = WhatLanguage.new(:all).language_iso('')
-        expect(result).to be_nil
+        result = CLD.detect_language('')
+        expect(result[:reliable]).to be false
       end
 
       describe 'because of a URL' do
         it 'uses default locale when sent just a URL' do
           string = 'http://example.com/media/2kFTgOJLXhQf0g2nKB4'
-          wl_result = WhatLanguage.new(:all).language_iso(string)
-          expect(wl_result).not_to eq :en
+          cld_result = CLD.detect_language(string)[:code]
+          expect(cld_result).not_to eq :en
 
           result = described_class.new(string).to_iso_s