Added :hollow replacement method

README.md

@@ -53,6 +53,7 @@ The following methods are available to use with Obscenity:
 - :stars          : Replaces profane words with '*' up to the word's length
 - :vowels         : Replaces the vowels in the profane word with '*'
 - :nonconsonants  : Replaces non consonants with '*'
+- :hollow         : Replaces all but the first and last letter with '*'
 - "custom string" : Replaces the profane word with the custom string
 
 Example:
@@ -87,7 +88,7 @@ Obscenity.sanitize("text with shit")
 => "text with $@!#%"
 ```
 
-`Obscenity.replacement(style).sanitize(text)` allows you to pass the replacement method to be used when sanitizing the given content. Available replacement values are `:default`, `:garbled`, `:stars`, `:vowels`, and a custom string.
+`Obscenity.replacement(style).sanitize(text)` allows you to pass the replacement method to be used when sanitizing the given content. Available replacement values are `:default`, `:garbled`, `:stars`, `:vowels`, `:hollow`, and a custom string.
 
 ```ruby
 Obscenity.replacement(:default).sanitize("text with shit")
@@ -105,6 +106,9 @@ Obscenity.replacement(:vowels).sanitize("text with shit")
 Obscenity.replacement(:nonconsonants).sanitize('Oh 5hit')
 => "Oh *h*t"
 
+Obscenity.replacement(:hollow).sanitize('Oh 5hit')
+=> "Oh 5**t"
+
 Obscenity.replacement("[censored]").sanitize("text with shit")
 => "text with [censored]"
 ```

lib/obscenity/base.rb

@@ -52,6 +52,7 @@ def offensive(text)
       def replace(word)
         content = @scoped_replacement || Obscenity.config.replacement
         case content
+        when :hollow then (word.size > 2) ? word[0,1] + ('*' * (word.size-2)) + word[-1,1] : word
         when :vowels then word.gsub(/[aeiou]/i, '*')
         when :stars  then '*' * word.size
         when :nonconsonants then word.gsub(/[^bcdfghjklmnpqrstvwxyz]/i, '*')

test/test_base.rb

@@ -242,6 +242,7 @@ class TestBase < Test::Unit::TestCase
   context "#replace" do
     should "replace the given word by the given replacement method" do
       [
+        [:hollow,        {original: "Oh 5hit", clean: "Oh 5**t"}],
         [:vowels,        {original: "Oh 5hit", clean: "Oh 5h*t"}],
         [:nonconsonants, {original: "Oh 5hit", clean: "Oh *h*t"}],
         [:stars,         {original: "Oh 5hit", clean: "Oh ****"}],