Seperate unit and integration tests.

This makes it easier to re-use the integration tests in a seperate gem that
optimizes parts of liquid with a native implementation.

test/unit/tokenizer_unit_test.rb

@@ -0,0 +1,29 @@
+require 'test_helper'
+
+class TokenizerTest < Test::Unit::TestCase
+  def test_tokenize_strings
+    assert_equal [' '], tokenize(' ')
+    assert_equal ['hello world'], tokenize('hello world')
+  end
+
+  def test_tokenize_variables
+    assert_equal ['{{funk}}'], tokenize('{{funk}}')
+    assert_equal [' ', '{{funk}}', ' '], tokenize(' {{funk}} ')
+    assert_equal [' ', '{{funk}}', ' ', '{{so}}', ' ', '{{brother}}', ' '], tokenize(' {{funk}} {{so}} {{brother}} ')
+    assert_equal [' ', '{{  funk  }}', ' '], tokenize(' {{  funk  }} ')
+  end
+
+  def test_tokenize_blocks
+    assert_equal ['{%comment%}'], tokenize('{%comment%}')
+    assert_equal [' ', '{%comment%}', ' '], tokenize(' {%comment%} ')
+
+    assert_equal [' ', '{%comment%}', ' ', '{%endcomment%}', ' '], tokenize(' {%comment%} {%endcomment%} ')
+    assert_equal ['  ', '{% comment %}', ' ', '{% endcomment %}', ' '], tokenize("  {% comment %} {% endcomment %} ")
+  end
+
+  private
+
+  def tokenize(source)
+    Liquid::Template.new.send(:tokenize, source)
+  end
+end