Move `unescape_html_entities` from LabelsHelper to Label model

app/helpers/labels_helper.rb

 module LabelsHelper
   include ActionView::Helpers::TagHelper
 
-  TABLE_FOR_ESCAPE_HTML_ENTITIES = {
-    '&' => '&',
-    '<' => '&lt;',
-    '>' => '&gt;'
-  }
-
   # Link to a Label
   #
   # label   - Label object to link to
@@ -136,11 +130,7 @@ module LabelsHelper
     label.subscribed?(current_user) ? 'Unsubscribe' : 'Subscribe'
   end
 
-  def unescape_html_entities(value)
-    value.to_s.gsub(/(&gt;)|(&lt;)|(&amp;)/, TABLE_FOR_ESCAPE_HTML_ENTITIES.invert)
-  end
-
   # Required for Banzai::Filter::LabelReferenceFilter
   module_function :render_colored_label, :render_colored_cross_project_label,
-                  :text_color_for_bg, :escape_once, :unescape_html_entities
+                  :text_color_for_bg, :escape_once
 end

app/models/label.rb

@@ -10,6 +10,12 @@ class Label < ActiveRecord::Base
 
   DEFAULT_COLOR = '#428BCA'
 
+  TABLE_FOR_ESCAPE_HTML_ENTITIES = {
+    '&' => '&amp;',
+    '<' => '&lt;',
+    '>' => '&gt;'
+  }
+
   default_value_for :color, DEFAULT_COLOR
 
   belongs_to :project
@@ -134,6 +140,10 @@ class Label < ActiveRecord::Base
   end
 
   def sanitize_title(value)
-    LabelsHelper.unescape_html_entities(Sanitize.clean(value.to_s))
+    unescape_html_entities(Sanitize.clean(value.to_s))
+  end
+
+  def unescape_html_entities(value)
+    value.to_s.gsub(/(&gt;)|(&lt;)|(&amp;)/, TABLE_FOR_ESCAPE_HTML_ENTITIES.invert)
   end
 end

lib/banzai/filter/label_reference_filter.rb

@@ -68,7 +68,7 @@ module Banzai
       end
 
       def unescape_html_entities(text)
-        LabelsHelper.unescape_html_entities(text)
+        text.to_s.gsub(/(>)|(<)|(&)/, Label::TABLE_FOR_ESCAPE_HTML_ENTITIES.invert)
       end
     end
   end

spec/helpers/labels_helper_spec.rb

@@ -77,10 +77,4 @@ describe LabelsHelper do
       expect(text_color_for_bg('#000')).to eq '#FFFFFF'
     end
   end
-
-  describe 'unescape_html_entities' do
-    it 'decodes &, <, and > named entities' do
-      expect(unescape_html_entities('foo &amp; bar &lt; zoo &gt; boo &eacute;')).to eq 'foo & bar < zoo > boo &eacute;'
-    end
-  end
 end