diff --git a/pythonbrew/commands/py.py b/pythonbrew/commands/py.py
index d6b90fa..1a052b9 100644
--- a/pythonbrew/commands/py.py
+++ b/pythonbrew/commands/py.py
@@ -4,7 +4,7 @@ from pythonbrew.basecommand import Command
 from pythonbrew.define import PATH_PYTHONS
 from pythonbrew.util import Package
 from pythonbrew.log import logger
-from subprocess import PIPE, Popen
+from subprocess import Popen
 
 class PyCommand(Command):
     name = "py"
diff --git a/pythonbrew/commands/switch.py b/pythonbrew/commands/switch.py
index 6ad1ffe..d553ccb 100644
--- a/pythonbrew/commands/switch.py
+++ b/pythonbrew/commands/switch.py
@@ -1,8 +1,8 @@
 import os
 import sys
 from pythonbrew.basecommand import Command
-from pythonbrew.define import PATH_PYTHONS, PATH_BIN, PATH_ETC_CURRENT
-from pythonbrew.util import Package
+from pythonbrew.define import PATH_PYTHONS, PATH_BIN
+from pythonbrew.util import Package, set_current_path
 from pythonbrew.log import logger
 
 class SwitchCommand(Command):
@@ -22,14 +22,8 @@ class SwitchCommand(Command):
             sys.exit(1)
         pkgbin = os.path.join(pkgdir,'bin')
         
-        self._set_current('%s:%s' % (PATH_BIN, pkgbin))
+        set_current_path('%s:%s' % (PATH_BIN, pkgbin))
         
         logger.info("Switched to %s" % pkgname)
-        
-    def _set_current(self, path):
-        fp = open(PATH_ETC_CURRENT, 'w')
-        fp.write('PATH_PYTHONBREW="%s"\n' % (path))
-        fp.close()
-
 
 SwitchCommand()
diff --git a/pythonbrew/commands/update.py b/pythonbrew/commands/update.py
index b17eb00..2462eb3 100644
--- a/pythonbrew/commands/update.py
+++ b/pythonbrew/commands/update.py
@@ -22,7 +22,7 @@ class UpdateCommand(Command):
         # check for latest version
         if version <= VERSION:
             logger.info("You are already running the installed latest version of pythonbrew.")
-            sys.exit()
+            return
         
         download_url = get_pythonbrew_update_url(version)
         if not download_url:
diff --git a/pythonbrew/installer.py b/pythonbrew/installer.py
index 585992e..32c0c15 100644
--- a/pythonbrew/installer.py
+++ b/pythonbrew/installer.py
@@ -4,7 +4,7 @@ import glob
 import shutil
 import re
 import mimetypes
-from pythonbrew.util import makedirs, symlink, Package, is_url, splitext, Link,\
+from pythonbrew.util import makedirs, symlink, Package, is_url, Link,\
     unlink, is_html, Subprocess, rm_r,\
     is_macosx_snowleopard, is_python25, is_python24, is_python26,\
     unpack_downloadfile, is_archive_file, path_to_fileurl, is_file,\
diff --git a/pythonbrew/util.py b/pythonbrew/util.py
index 9b83163..3491017 100644
--- a/pythonbrew/util.py
+++ b/pythonbrew/util.py
@@ -8,8 +8,7 @@ import tarfile
 import platform
 import urllib
 from subprocess import PIPE, Popen
-from pythonbrew.define import PATH_BIN, PATH_PYTHONS, PATH_ETC_CURRENT,\
-    PATH_ETC_TEMP
+from pythonbrew.define import PATH_BIN, PATH_PYTHONS, PATH_ETC_CURRENT
 from pythonbrew.exceptions import ShellCommandException
 from pythonbrew.log import logger
 
@@ -108,7 +107,7 @@ def off():
                 continue
             unlink("%s/%s" % (root, f))
     unlink("%s/current" % PATH_PYTHONS)
-    write_current(PATH_BIN)
+    set_current_path(PATH_BIN)
 
 def split_leading_dir(path):
     path = str(path)
@@ -202,6 +201,11 @@ def get_current_python_path():
     else:
         return None
 
+def set_current_path(path):
+    fp = open(PATH_ETC_CURRENT, 'w')
+    fp.write('PATH_PYTHONBREW="%s"\n' % (path))
+    fp.close()
+
 def path_to_fileurl(path):
     path = os.path.normcase(os.path.abspath(path))
     url = urllib.quote(path)
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..d21f0fd
--- /dev/null
+++ b/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()
diff --git a/tests/test_00_install_pythonbrew.py b/tests/test_00_install_pythonbrew.py
new file mode 100644
index 0000000..bef3c06
--- /dev/null
+++ b/tests/test_00_install_pythonbrew.py
@@ -0,0 +1,3 @@
+def test_install_pythonbrew():
+    from pythonbrew.installer import install_pythonbrew
+    install_pythonbrew()
diff --git a/tests/test_01_update.py b/tests/test_01_update.py
new file mode 100644
index 0000000..884c11e
--- /dev/null
+++ b/tests/test_01_update.py
@@ -0,0 +1,5 @@
+def test_update():
+    from pythonbrew.commands.update import UpdateCommand
+    c = UpdateCommand()
+    c.run_command(None, None)
+    
\ No newline at end of file
diff --git a/tests/test_02_help.py b/tests/test_02_help.py
new file mode 100644
index 0000000..be0c836
--- /dev/null
+++ b/tests/test_02_help.py
@@ -0,0 +1,4 @@
+def test_help():
+    from pythonbrew.commands.help import HelpCommand
+    c = HelpCommand()
+    c.run_command(None, None)
diff --git a/tests/test_03_version.py b/tests/test_03_version.py
new file mode 100644
index 0000000..1db366a
--- /dev/null
+++ b/tests/test_03_version.py
@@ -0,0 +1,4 @@
+def test_version():
+    from pythonbrew.commands.version import VersionCommand
+    c = VersionCommand()
+    c.run_command(None, None)
diff --git a/tests/test_04_install.py b/tests/test_04_install.py
new file mode 100644
index 0000000..0b1722f
--- /dev/null
+++ b/tests/test_04_install.py
@@ -0,0 +1,11 @@
+from tests import TESTPY_VERSION
+
+class InstallOptions(object):
+    force = True
+    configure = ""
+    no_setuptools = False
+
+def test_install():
+    from pythonbrew.commands.install import InstallCommand
+    c = InstallCommand()
+    c.run_command(InstallOptions(), [TESTPY_VERSION])
diff --git a/tests/test_05_switch.py b/tests/test_05_switch.py
new file mode 100644
index 0000000..e6d9fe2
--- /dev/null
+++ b/tests/test_05_switch.py
@@ -0,0 +1,6 @@
+from tests import TESTPY_VERSION
+
+def test_switch():
+    from pythonbrew.commands.switch import SwitchCommand
+    c = SwitchCommand()
+    c.run_command(None, [TESTPY_VERSION])
diff --git a/tests/test_06_use.py b/tests/test_06_use.py
new file mode 100644
index 0000000..ebd5ce3
--- /dev/null
+++ b/tests/test_06_use.py
@@ -0,0 +1,6 @@
+from tests import TESTPY_VERSION
+
+def test_use():
+    from pythonbrew.commands.use import UseCommand
+    c = UseCommand()
+    c.run_command(None, [TESTPY_VERSION])
diff --git a/tests/test_07_off.py b/tests/test_07_off.py
new file mode 100644
index 0000000..60e9f65
--- /dev/null
+++ b/tests/test_07_off.py
@@ -0,0 +1,4 @@
+def test_off():
+    from pythonbrew.commands.off import OffCommand
+    c = OffCommand()
+    c.run_command(None, None)
diff --git a/tests/test_08_list.py b/tests/test_08_list.py
new file mode 100644
index 0000000..7d5ab7e
--- /dev/null
+++ b/tests/test_08_list.py
@@ -0,0 +1,8 @@
+class ListOptions(object):
+    all_versions = False
+    known = False
+
+def test_list():
+    from pythonbrew.commands.list import ListCommand
+    c = ListCommand()
+    c.run_command(ListOptions(), None)
diff --git a/tests/test_09_py.py b/tests/test_09_py.py
new file mode 100644
index 0000000..54f7e8c
--- /dev/null
+++ b/tests/test_09_py.py
@@ -0,0 +1,10 @@
+from tests import TESTPY_FILE
+
+class PyOptions(object):
+    pythons = []
+    verbose = False
+
+def test_py():
+    from pythonbrew.commands.py import PyCommand
+    c = PyCommand()
+    c.run_command(PyOptions(), [TESTPY_FILE])
diff --git a/tests/test_10_uninstall.py b/tests/test_10_uninstall.py
new file mode 100644
index 0000000..3327b77
--- /dev/null
+++ b/tests/test_10_uninstall.py
@@ -0,0 +1,6 @@
+from tests import TESTPY_VERSION
+
+def test_uninstall():
+    from pythonbrew.commands.uninstall import UninstallCommand
+    c = UninstallCommand()
+    c.run_command(None, [TESTPY_VERSION])
diff --git a/tests/test_11_clean.py b/tests/test_11_clean.py
new file mode 100644
index 0000000..7823339
--- /dev/null
+++ b/tests/test_11_clean.py
@@ -0,0 +1,4 @@
+def test_clean():
+    from pythonbrew.commands.clean import CleanCommand
+    c = CleanCommand()
+    c.run_command(None, None)