Run the tutorial inside the test suite.

Until the other tutorial files are fixed this just tests 0-introduction.txt.

NEWS

@@ -16,6 +16,8 @@
   * Support parsing git mbox patches without a version tail, as generated by
     Mercurial.  (Jelmer Vernooij)
 
+  * Run the tutorial inside the test suite. (Jelmer Vernooij)
+
 0.6.2	2010-10-16
 
  BUG FIXES

dulwich/tests/__init__.py

@@ -19,6 +19,8 @@
 
 """Tests for Dulwich."""
 
+import doctest
+import os
 import unittest
 
 try:
@@ -74,4 +76,10 @@ def test_suite():
     loader = unittest.TestLoader()
     suite = loader.loadTestsFromNames(module_names)
     result.addTests(suite)
+    tutorial = [
+        '0-introduction',
+        ]
+    tutorial_files = ["../../docs/tutorial/%s.txt" % name for name in tutorial]
+    suite = doctest.DocFileSuite(*tutorial_files)
+    result.addTests(suite)
     return result