Add exclude_words filter to Faker::Lorem.word generator (#2761)

* Add exclude_words keyword to Lorem Ipsum word

* Reuse words() method and reduce word generation in tests

Author: Geophilus Durairaj

doc/default/lorem.md

@@ -1,7 +1,11 @@
 # Faker::Lorem
 
 ```ruby
+# Keyword arguments: exclude_words (prevent specific words from being produced)
 Faker::Lorem.word #=> "repellendus"
+Faker::Lorem.word(exclude_words: 'error') #=> "nisi"
+Faker::Lorem.word(exclude_words: 'id, error') #=> "et"
+Faker::Lorem.word(exclude_words: ['id', 'error']) #=> "consequatur"
 
 # Keyword arguments: number, supplemental (words from a supplementary list of Lorem-like words)
 Faker::Lorem.words #=> ["dolores", "adipisci", "nesciunt"]

lib/faker/default/lorem.rb

@@ -10,10 +10,13 @@ class << self
       #
       # @example
       #   Faker::Lorem.word   #=> "soluto"
+      #   Faker::Lorem.word(exclude_words: 'error') #=> "nisi"
+      #   Faker::Lorem.word(exclude_words: 'id, error') #=> "et"
+      #   Faker::Lorem.word(exclude_words: ['id', 'error']) #=> "consequatur"
       #
       # @faker.version 2.1.3
-      def word
-        sample(translate('faker.lorem.words'))
+      def word(exclude_words: nil)
+        words(number: 1, exclude_words: exclude_words).first
       end
 
       ##

test/faker/default/test_faker_lorem.rb

@@ -48,12 +48,28 @@ def test_supplemental_words
 
   # Faker::Lorem.word generates random word from standard wordlist
   def test_word
-    @tester = Faker::Lorem
     @standard_wordlist = I18n.translate('faker.lorem.words')
 
     100.times { assert_includes @standard_wordlist, @tester.word }
   end
 
+  def test_excluded_words_on_word
+    excluded_words_array = @tester.words(number: 2)
+    w = @tester.word(exclude_words: excluded_words_array)
+
+    assert_not_equal w, excluded_words_array[0]
+    assert_not_equal w, excluded_words_array[1]
+  end
+
+  def test_excluded_words_as_string_on_word
+    excluded_words_array = @tester.words(number: 2)
+    excluded_word_string = excluded_words_array.join(', ')
+    w = @tester.word(exclude_words: excluded_word_string)
+
+    assert_not_equal w, excluded_words_array[0]
+    assert_not_equal w, excluded_words_array[1]
+  end
+
   def test_exact_sentence_word_count
     assert_equal 2, @tester.sentence(word_count: 2, supplemental: false, random_words_to_add: 0).split.length
   end