add per-step failure support for WiFi tests

server/site_wifitest.py

 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import common, fnmatch, logging, os, re, string, threading, time
 
 from autotest_lib.server import autotest, hosts, subcommand
 from autotest_lib.server import site_bsd_router
 from autotest_lib.server import site_linux_router
 from autotest_lib.server import site_host_attributes
@@ skipping 168 matching lines @@
         # Calculate ssid based on test name; this lets us track progress
         # by watching beacon frames.
         #
         return re.sub('[^a-zA-Z0-9_]', '_', "%s_%s" % (self.name, ipaddr))
 
 
     def run(self):
         """
         Run a WiFi test.  Each step is interpreted as a method either
         in this class or the ancillary router class and invoked with
-        the supplied parameter dictionary.
+        the supplied parameter dictionary.  If the method is prefixed
+        with '!' then we expect the operation to fail; this is useful,
+        for example, for testing parameter checking in flimflam.
         """
         for s in self.steps:
             method = s[0]
+            if method[0] == '!':
+                expect_failure = True
+                method = method[1:]
+            else:
+                expect_failure = False
             if len(s) > 1:
                 params = s[1]
             else:
                 params = {}
 
             # What should perf data be prefixed with?
             if 'perf_prefix' in params:
                 self.prefix = '%s_%s' % (method, params.pop('perf_prefix'))
             elif method in self.iterated_steps:
                 self.prefix = '%s_%d' % (method, self.iterated_steps[method])
                 self.iterated_steps[method] += 1
             else:
                 self.prefix = method
 
-            logging.info("%s: step '%s' params %s", self.name, method, params)
+            if expect_failure is True:
+                logging.info("%s: step '%s' (expect failure)  params %s",
+                    self.name, method, params)
+            else:
+                logging.info("%s: step '%s' params %s", self.name, method,
+                    params)
 
             func = getattr(self, method, None)
             if func is None:
                 func = getattr(self.wifi, method, None)
             if func is not None:
                 try:
                     func(params)
+                    if expect_failure is True:
+                        raise error.TestFail("Expected failure")
                 except Exception, e:
+                    if expect_failure is True:
+                        continue
                     logging.error("%s: Step '%s' failed: %s; abort test",
                         self.name, method, str(e))
                     self.cleanup(params)
                     raise e
-                    break
             else:
                 logging.error("%s: Step '%s' unknown; abort test",
                     self.name, method)
                 self.cleanup(params)
                 break
 
         # Other cleanup steps might be optional, but this is mandatory
         self.client_netdump_stop({})
 
 
@@ skipping 633 matching lines @@
     except error.TestFail:
       if 'expect_failure' in testcase:
         self.expect_failure(name, testcase['expect_failure'])
       else:
         raise
     except Exception, e:
       if 'expect_failure' in testcase:
         self.expect_failure(name, testcase['expect_failure'])
       else:
         raise error.TestFail(e)