Extensions aren't actually required

lib/linguist/language.rb

@@ -595,9 +595,9 @@ module Linguist
       :ace_mode          => options['ace_mode'],
       :wrap              => options['wrap'],
       :group_name        => options['group'],
-      :searchable        => options.key?('searchable') ? options['searchable'] : true,
+      :searchable        => options.fetch('searchable', true),
       :search_term       => options['search_term'],
-      :extensions        => [options['extensions'].first] + options['extensions'][1..-1].sort,
+      :extensions        => Array(options['extensions']),
       :interpreters      => options['interpreters'].sort,
       :filenames         => options['filenames'],
       :popular           => popular.include?(name)

test/test_language.rb

@@ -349,12 +349,6 @@ class TestLanguage < Test::Unit::TestCase
     assert_equal '.coffee', Language['CoffeeScript'].primary_extension
     assert_equal '.t', Language['Turing'].primary_extension
     assert_equal '.ts', Language['TypeScript'].primary_extension
-
-    # This is a nasty requirement, but there's some code in GitHub that
-    # expects this. Really want to drop this.
-    Language.all.each do |language|
-      assert language.primary_extension, "#{language} has no primary extension"
-    end
   end
 
   def test_eql