diff --git a/features/test/prettify_test.py b/features/test/prettify_test.py
new file mode 100644
index 0000000..07fce43
--- /dev/null
+++ b/features/test/prettify_test.py
@@ -0,0 +1,92 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file or at
+# https://developers.google.com/open-source/licenses/bsd
+
+"""Unittest for the prettify module."""
+from __future__ import print_function
+from __future__ import division
+from __future__ import absolute_import
+
+import unittest
+
+import ezt
+
+from features import prettify
+
+
+class SourceBrowseTest(unittest.TestCase):
+
+  def testPrepareSourceLinesForHighlighting(self):
+    # String representing an empty source file
+    src = ''
+
+    file_lines = prettify.PrepareSourceLinesForHighlighting(src)
+    self.assertEqual(len(file_lines), 0)
+
+  def testPrepareSourceLinesForHighlightingNoBreaks(self):
+    # seven lines of text with no blank lines
+    src = ' 1\n 2\n 3\n 4\n 5\n 6\n 7'
+
+    file_lines = prettify.PrepareSourceLinesForHighlighting(src)
+    self.assertEqual(len(file_lines), 7)
+    out_lines = [fl.line for fl in file_lines]
+    self.assertEqual('\n'.join(out_lines), src)
+
+    file_lines = prettify.PrepareSourceLinesForHighlighting(src)
+    self.assertEqual(len(file_lines), 7)
+
+  def testPrepareSourceLinesForHighlightingWithBreaks(self):
+    # seven lines of text with line 5 being blank
+    src = ' 1\n 2\n 3\n 4\n\n 6\n 7'
+
+    file_lines = prettify.PrepareSourceLinesForHighlighting(src)
+    self.assertEqual(len(file_lines), 7)
+
+
+class BuildPrettifyDataTest(unittest.TestCase):
+
+  def testNonSourceFile(self):
+    prettify_data = prettify.BuildPrettifyData(0, '/dev/null')
+    self.assertDictEqual(
+        dict(should_prettify=ezt.boolean(False),
+             prettify_class=None),
+        prettify_data)
+
+    prettify_data = prettify.BuildPrettifyData(10, 'readme.txt')
+    self.assertDictEqual(
+        dict(should_prettify=ezt.boolean(False),
+             prettify_class=None),
+        prettify_data)
+
+  def testGenericLanguage(self):
+    prettify_data = prettify.BuildPrettifyData(123, 'trunk/src/hello.php')
+    self.assertDictEqual(
+        dict(should_prettify=ezt.boolean(True),
+             prettify_class=''),
+        prettify_data)
+
+  def testSpecificLanguage(self):
+    prettify_data = prettify.BuildPrettifyData(123, 'trunk/src/hello.java')
+    self.assertDictEqual(
+        dict(should_prettify=ezt.boolean(True),
+             prettify_class='lang-java'),
+        prettify_data)
+
+  def testThirdPartyExtensionLanguages(self):
+    for ext in ['apollo', 'agc', 'aea', 'el', 'scm', 'cl', 'lisp',
+                'go', 'hs', 'lua', 'fs', 'ml', 'proto', 'scala',
+                'sql', 'vb', 'vbs', 'vhdl', 'vhd', 'wiki', 'yaml',
+                'yml', 'clj']:
+      prettify_data = prettify.BuildPrettifyData(123, '/trunk/src/hello.' + ext)
+      self.assertDictEqual(
+          dict(should_prettify=ezt.boolean(True),
+               prettify_class='lang-' + ext),
+          prettify_data)
+
+  def testExactFilename(self):
+    prettify_data = prettify.BuildPrettifyData(123, 'trunk/src/Makefile')
+    self.assertDictEqual(
+        dict(should_prettify=ezt.boolean(True),
+             prettify_class='lang-sh'),
+        prettify_data)