Add vi locale

README.markdown

@@ -94,6 +94,7 @@ Currently supported locales:
 * Portuguese: `:pt`
 * Malaysia `:ms`
 * Japanese `:jp`
+* Vietnamese `:vi`
 
 ## Testing
 

lib/humanize.rb

@@ -30,7 +30,7 @@ def humanize(locale: Humanize.config.default_locale,
   def self.for_locale(locale)
     case locale.to_sym
     # NOTE: add locales here in ealphabetical order
-    when :az, :de, :en, :es, :fr, :id, :ms, :pt, :ru
+    when :az, :de, :en, :es, :fr, :id, :ms, :pt, :ru, :vi
       [Object.const_get("Humanize::#{locale.capitalize}"), SPACE]
     when :th
       [Humanize::Th, EMPTY]

lib/humanize/locales.rb

@@ -1,5 +1,5 @@
 module Humanize
-  %w[az de en es fr id ms pt ru th tr jp].each do |locale|
+  %w[az de en es fr id ms pt ru th tr jp vi].each do |locale|
     autoload locale.capitalize.to_sym, "humanize/locales/#{locale}.rb"
   end
 end

lib/humanize/locales/vi.rb

@@ -0,0 +1,35 @@
+require_relative 'constants/vi'
+
+module Humanize
+  class Vi
+    def humanize(number)
+      iteration = 0
+      parts = []
+      until number.zero?
+        number, remainder = number.divmod(1000)
+
+        if !remainder.zero?
+          parts << LOTS[iteration] if iteration.positive?
+          parts << SUB_ONE_GROUPING[remainder]
+          add_linked_word(parts, remainder) if number.positive?
+        elsif iteration.positive? && (iteration % 3).zero?
+          parts << LOTS[3]
+        end
+
+        iteration += 1
+      end
+
+      parts
+    end
+
+    private
+
+    def add_linked_word(parts, remainder)
+      if remainder < 10
+        parts << LINKED_WORDS[0]
+      elsif remainder < 100
+        parts << LINKED_WORDS[1]
+      end
+    end
+  end
+end