Clobber layout test results at the beginning of each run....

webkit/tools/layout_tests/run_webkit_tests.py

 #!/usr/bin/env python
 # Copyright (c) 2006-2009 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Run layout tests using the test_shell.
 
 This is a port of the existing webkit test script run-webkit-tests.
 
 The TestRunner class runs a series of tests (TestType interface) against a set
@@ skipping 1013 matching lines @@
     # Assume it's an absolute path and normalize.
     options.results_directory = path_utils.GetAbsolutePath(
         options.results_directory)
   else:
     # If it's a relative path, make the output directory relative to Debug or
     # Release.
     basedir = path_utils.PathFromBase('webkit')
     options.results_directory = path_utils.GetAbsolutePath(
         os.path.join(basedir, options.target, options.results_directory))
 
+  if options.clobber_old_results:
+    # Just clobber the actual test results directories since the other files
+    # in the results directory are explicitly used for cross-run tracking.
+    test_dirs = ["LayoutTests", "chrome", "pending"]

[tony, 2009/11/02 19:36:54]

Nit: Use () instead of [] to make it immutable.

+    for directory in test_dirs:
+      path = os.path.join(options.results_directory, directory)
+      if os.path.exists(path):
+        shutil.rmtree(path)
+
   # Ensure platform is valid and force it to the form 'chromium-<platform>'.
   options.platform = path_utils.PlatformName(options.platform)
 
   if not options.num_test_shells:
     cpus = 1
     if sys.platform in ('win32', 'cygwin'):
       cpus = int(os.environ.get('NUMBER_OF_PROCESSORS', 1))
     elif (hasattr(os, "sysconf") and
           os.sysconf_names.has_key("SC_NPROCESSORS_ONLN")):
       # Linux & Unix:
@@ skipping 122 matching lines @@
                            default=False,
                            help="save all generated results as new baselines "
                                 "into the platform directory, overwriting "
                                 "whatever's already there.")
   option_parser.add_option("", "--noshow-results", action="store_true",
                            default=False, help="don't launch the test_shell"
                            " with results after the tests are done")
   option_parser.add_option("", "--full-results-html", action="store_true",
                            default=False, help="show all failures in "
                            "results.html, rather than only regressions")
+  option_parser.add_option("", "--clobber-old-results", action="store_true",
+                           default=False, help="Clobbers test results from "
+                           "previous runs.")
   option_parser.add_option("", "--lint-test-files", action="store_true",
                            default=False, help="Makes sure the test files "
                            "parse for all configurations. Does not run any "
                            "tests.")
   option_parser.add_option("", "--force", action="store_true",
                            default=False,
                            help="Run all tests, even those marked SKIP in the "
                                 "test list")
   option_parser.add_option("", "--nocompare-failures", action="store_true",
                            default=False,
@@ skipping 70 matching lines @@
                                  "this script."))
   option_parser.add_option("", "--find-baselines", action="store_true",
                            default=False,
                            help="Prints a table mapping tests to their "
                                 "expected results")
   option_parser.add_option("", "--experimental-fully-parallel",
                            action="store_true", default=False,
                            help="run all tests in parallel")
   options, args = option_parser.parse_args()
   main(options, args)