Use unittest framework in the Automated Installer Testing Framework.

chrome/test/mini_installer/test_installer.py

Index: chrome/test/mini_installer/test_installer.py
diff --git a/chrome/test/mini_installer/test_installer.py b/chrome/test/mini_installer/test_installer.py
index a59bf9164074f3706728b0b4042490dfee34f2c3..2c41e934bb92862b2a6d102495abf928dc57ca1b 100644
--- a/chrome/test/mini_installer/test_installer.py
+++ b/chrome/test/mini_installer/test_installer.py
@@ -13,8 +13,8 @@ import argparse
 import json
 import os
 import subprocess
+import unittest
 
-import settings
 import verifier
 
 
@@ -34,6 +34,73 @@ class Config:
     self.tests = []
 
 
+class InstallerTest(unittest.TestCase):
+  """Tests a test case in the config file."""
+
+  def __init__(self, test, config):
+    """Constructor.
+
+    Args:
+      test: An array of alternating state names and action names, starting and
+          ending with state names.
+      config: The Config object.
+    """
+    super(InstallerTest, self).__init__()
+    self.test = test
+    self.config = config
+
+  def runTest(self):
+    """Run the test case."""
+    test = self.test
+
+    # |test| is an array of alternating state names and action names, starting
+    # and ending with state names. Therefore, its length must be odd.
+    self.assertEqual(len(test) % 2, 1, 'The length of test array must be odd')
+
+    self._RunResetCommand()
+
+    current_state = test[0]
+    self._VerifyState(current_state)
+
+    for i in range(1, len(test), 2):
+      action = test[i]
+      self._RunCommand(self.config.actions[action])
+
+      current_state = test[i + 1]
+      self._VerifyState(current_state)
+
+  def __str__(self):
+    return 'Test: %s' % ('-> '.join(self.test))
+
+  def shortDescription(self):
+    """Returns None as the short description to suppress its printing.
+
+    The default implementation of this method returns the docstring of the
+    runTest method, which is not useful since it's the same for every test case.
+    The description from the __str__ method is informative enough.
+    """
+    return None
+
+  def _VerifyState(self, state):
+    """Verifies that the current machine states match the given machine states.
+
+    Args:
+      state: The current state.
+    """
+    try:
+      verifier.Verify(self.config.states[state], self)
+    except AssertionError as e:
+      error_msg = "In state '%s', %s" % (state, e)

[robertshield, 2013/08/06 21:42:22]

It seems like the whole config struct is passed down to the verifier already
(the self parameter contains the config) so the information needed to display
this message is already available to the verifier code.

Given this, do we need to catch the AssertionError here to add the state
information?

[sukolsak, 2013/08/06 23:43:06]

True, but I would like to keep the assertions as simple as possible, e.g.
testcase.AssertTrue(..., msg) instead of testcase.AssertTrue(...,
testcase.current_state + ', ' + msg).

It looks like failureException is exactly what we want.
http://docs.python.org/2/library/unittest.html#unittest.TestCase.failureExcep...

+      raise AssertionError(error_msg)
+
+  def _RunCommand(self, command):
+    subprocess.call(command, shell=True)
+
+  def _RunResetCommand(self):
+    # TODO(sukolsak): Need to figure how exactly we want to reset.
+    pass
+
+
 def MergePropertyDictionaries(current_property, new_property):
   """Merges the new property dictionary into the current property dictionary.
 
@@ -100,54 +167,16 @@ def ParseConfigFile(filename):
   return config
 
 
-def VerifyState(config, state):
-  """Verifies that the current machine states match the given machine states.
-
-  Args:
-    config: A Config object.
-    state: The current state.
-  """
-  # TODO(sukolsak): Think of ways of preserving the log when the test fails but
-  # not printing these when the test passes.
-  print settings.PRINT_STATE_PREFIX + state
-  verifier.Verify(config.states[state])
-
-
-def RunCommand(command):
-  print settings.PRINT_COMMAND_PREFIX + command
-  subprocess.call(command, shell=True)
-
-
-def RunResetCommand():
-  print settings.PRINT_COMMAND_PREFIX + 'Reset'
-  # TODO(sukolsak): Need to figure how exactly we want to reset.
-
-
 def Test(config):
   """Tests the installer using the given Config object.
 
   Args:
     config: A Config object.
   """
+  suite = unittest.TestSuite()
   for test in config.tests:
-    print settings.PRINT_TEST_PREFIX + ' -> '.join(test)
-
-    # A Test object is an array of alternating state names and action names.
-    # The array starts and ends with states. Therefore, the length must be odd.
-    assert(len(test) % 2 == 1)
-
-    RunResetCommand()
-
-    current_state = test[0]
-    VerifyState(config, current_state)
-    # TODO(sukolsak): Quit the test early if VerifyState fails at any point.
-
-    for i in range(1, len(test), 2):
-      action = test[i]
-      RunCommand(config.actions[action])
-
-      current_state = test[i + 1]
-      VerifyState(config, current_state)
+    suite.addTest(InstallerTest(test, config))
+  unittest.TextTestRunner(verbosity=2).run(suite)
 
 
 def main():