Bug fixed. Added tests.

tests/__init__.py

@@ -0,0 +1,21 @@
+import os
+import shutil
+
+PYTHONBREW_ROOT = '/tmp/pythonbrew.test'
+TESTPY_FILE = '/tmp/pythonbrew_test.py'
+TESTPY_VERSION = '2.6.6'
+def cleanall():
+    if os.path.isdir(PYTHONBREW_ROOT):
+        shutil.rmtree(PYTHONBREW_ROOT)
+    if os.path.isfile(TESTPY_FILE):
+        os.remove(TESTPY_FILE)
+
+def setup():
+    os.environ['PYTHONBREW_ROOT'] = PYTHONBREW_ROOT
+    cleanall()
+    fp = open(TESTPY_FILE, 'w')
+    fp.write("print 'test'")
+    fp.close()
+    
+def teardown():
+    cleanall()