Add sketch of I18n error translation

test/fixtures/en_locale.yml

@@ -0,0 +1,9 @@
+---
+  simple: "less is more"
+  whatever: "something :something"
+  errors:
+    i18n:
+      undefined_interpolation: "undefined key :key"
+      unknown_translation: "translation ':name' wasn't found"
+    syntax:
+      oops: "something wasn't right"

test/liquid/i18n_test.rb

@@ -0,0 +1,33 @@
+require 'test_helper'
+
+class I18nTest < Test::Unit::TestCase
+  include Liquid
+
+  def setup
+    @i18n = I18n.new("./test/fixtures/en_locale.yml")
+  end
+
+  def test_simple_translate_string
+    assert_equal "less is more", @i18n.translate("simple")
+  end
+
+  def test_nested_translate_string
+    assert_equal "something wasn't right", @i18n.translate("errors.syntax.oops")
+  end
+
+  def test_single_string_interpolation
+    assert_equal "something different", @i18n.translate("whatever", :something => "different")
+  end
+
+  def test_raises_keyerror_on_undefined_interpolation_key
+    assert_raise I18n::TranslationError do
+      @i18n.translate("whatever", :oopstypos => "yes")
+    end
+  end
+  
+  def test_raises_unknown_translation
+    assert_raise I18n::TranslationError do
+      @i18n.translate("doesnt_exist")
+    end
+  end
+end

test/test_helper.rb

@@ -7,7 +7,9 @@ begin
 rescue LoadError
   puts "Couldn't load ruby-debug. gem install ruby-debug if you need it."
 end
-require File.join(File.dirname(__FILE__), '..', 'lib', 'liquid')
+
+$:.unshift(File.join(File.expand_path(File.dirname(__FILE__)), '..', 'lib'))
+require 'liquid.rb'
 
 mode = :strict
 if env_mode = ENV['LIQUID_PARSER_MODE']