Implemented references for keys. Closes #82.

README.md

@@ -35,6 +35,10 @@ Tags are used by Twine as a way to only work with a subset of your strings at an
 
 Whitepace in this file is mostly ignored. If you absolutely need to put spaces at the beginning or end of your translated string, you can wrap the entire string in a pair of `` ` `` characters. If your actual string needs to start *and* end with a grave accent, you can wrap it in another pair of `` ` `` characters. See the example, below.
 
+### References
+
+If you want a key to inherit the values of another key, you can use a reference. Any property not specified for a key will be taken from the reference.
+
 ### Example
 
 	[[General]]
@@ -57,6 +61,9 @@ Whitepace in this file is mostly ignored. If you absolutely need to put spaces a
 			en = The network is currently unavailable.
 			tags = app1
 			comment = An error describing when the device can not connect to the internet.
+		[dismiss_error]
+			ref = [yes]
+			en = Dismiss
 
 	[[Escaping Example]]
 		[list_item_separator]

lib/twine/stringsfile.rb

@@ -14,6 +14,7 @@ module Twine
     attr_accessor :comment
     attr_accessor :tags
     attr_reader :translations
+    attr_accessor :reference
 
     def initialize(key)
       @key = key
@@ -22,13 +23,19 @@ module Twine
       @translations = {}
     end
 
+    def comment
+      @comment || (reference.comment if reference)
+    end
+
     def matches_tags?(tags, include_untagged)
-      if tags == nil || tags.length == 0
+      if tags == nil || tags.empty?
         # The user did not specify any tags. Everything passes.
         return true
-      elsif @tags == nil || @tags.length == 0
+      elsif @tags == nil
         # This row has no tags.
-        return (include_untagged) ? true : false
+        return reference ? reference.matches_tags?(tags, include_untagged) : include_untagged
+      elsif @tags.empty?
+        return include_untagged
       else
         tags.each do |tag|
           if @tags.include? tag
@@ -42,6 +49,9 @@ module Twine
 
     def translated_string_for_lang(lang, default_lang=nil)
       translation = [lang].flatten.map { |l| @translations[l] }.first
+
+      translation = reference.translated_string_for_lang(lang, default_lang) if translation.nil? && reference
+
       return translation if translation
       
       # TODO: get rid of all this and the default_lang parameter once all formatters are converted to the new style
@@ -63,6 +73,15 @@ module Twine
     attr_reader :strings_map
     attr_reader :language_codes
 
+    private
+
+    def match_key(text)
+      match = /^\[(.+)\]$/.match(text)
+      return match[1] if match
+    end
+
+    public
+
     def initialize
       @sections = []
       @strings_map = {}
@@ -95,9 +114,9 @@ module Twine
               parsed = true
             end
           elsif line.length > 2 && line[0, 1] == '['
-            match = /^\[(.+)\]$/.match(line)
-            if match
-              current_row = StringsRow.new(match[1])
+            key = match_key(line)
+            if key
+              current_row = StringsRow.new(key)
               @strings_map[current_row.key] = current_row
               if !current_section
                 current_section = StringsSection.new('')
@@ -116,10 +135,13 @@ module Twine
               end
 
               case key
-              when "comment"
+              when 'comment'
                 current_row.comment = value
               when 'tags'
                 current_row.tags = value.split(',')
+              when 'ref'
+                key = match_key(value)
+                current_row.reference = key if key
               else
                 if !@language_codes.include? key
                   add_language_code(key)
@@ -135,6 +157,12 @@ module Twine
           end
         end
       end
+
+      # resolve_references
+      @strings_map.each do |key, row|
+        next unless row.reference
+        row.reference = @strings_map[row.reference]
+      end
     end
 
     def write(path)

test/fixtures/strings-4-references.txt

@@ -0,0 +1,20 @@
+[[General]]
+  [key1]
+    en = key1-english
+    tags = tag1
+    comment = This is a comment
+    es = key1-spanish
+    fr = key1-french
+
+[[My Strings]]
+  [key2]
+    ref = [key1]
+  [key3]
+    ref = [key1]
+    fr = key3-french
+  [key4]
+    ref = [key1]
+    comment = Different comment
+  [key5]
+    ref = [key1]
+    tags = tag2

test/fixtures/test-output-14-references.txt

@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Android Strings File -->
+<!-- Generated by Twine <%= Twine::VERSION %> -->
+<!-- Language: fr -->
+<resources>
+	<!-- SECTION: General -->
+	<!-- This is a comment -->
+	<string name="key1">key1-french</string>
+
+	<!-- SECTION: My Strings -->
+	<!-- This is a comment -->
+	<string name="key2">key1-french</string>
+	<!-- This is a comment -->
+	<string name="key3">key3-french</string>
+	<!-- Different comment -->
+	<string name="key4">key1-french</string>
+</resources>

test/twine_test.rb

@@ -147,4 +147,12 @@ class TwineTest < Test::Unit::TestCase
       assert_equal(ERB.new(File.read('test/fixtures/test-output-14.txt')).result, File.read(output_path))
     end
   end
+
+  def test_generate_string_file_14_references
+    Dir.mktmpdir do |dir|
+      output_path = File.join(dir, 'references.xml')
+      Twine::Runner.run(%W(generate-string-file test/fixtures/strings-4-references.txt #{output_path} -l fr -t tag1))
+      assert_equal(ERB.new(File.read('test/fixtures/test-output-14-references.txt')).result, File.read(output_path))
+    end
+  end  
 end