webkitpy: Prevent the addition of duplicate virtual tests.

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/base.py

 # Copyright (C) 2010 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 1463 matching lines @@
             # PhysicalTestSuite('svg', ['--force-compositing-mode']),
             PhysicalTestSuite('fast/text', ['--enable-direct-write', '--enable-font-antialiasing']),
         ]
 
     def virtual_test_suites(self):
         if self._virtual_test_suites is None:
             path_to_virtual_test_suites = self._filesystem.join(self.layout_tests_dir(), 'VirtualTestSuites')
             assert self._filesystem.exists(path_to_virtual_test_suites), 'LayoutTests/VirtualTestSuites not found'
             try:
                 test_suite_json = json.loads(self._filesystem.read_text_file(path_to_virtual_test_suites))
-                self._virtual_test_suites = [VirtualTestSuite(**d) for d in test_suite_json]
+                self._virtual_test_suites = []
+                for json_config in test_suite_json:
+                    vts = VirtualTestSuite(**json_config)
+                    if vts in self._virtual_test_suites:
+                        raise ValueError('LayoutTests/VirtualTestSuites contains duplicate definition: %r' % json_config)
+                    self._virtual_test_suites.append(vts)
             except ValueError as error:
                 raise ValueError('LayoutTests/VirtualTestSuites is not a valid JSON file: %s' % error)
         return self._virtual_test_suites
 
     def _all_virtual_tests(self, suites):
         tests = []
         for suite in suites:
             self._populate_virtual_suite(suite)
             tests.extend(suite.tests.keys())
         return tests
@@ skipping 115 matching lines @@
         assert '/' not in prefix, "Virtual test suites prefixes cannot contain /'s: %s" % prefix
         self.name = 'virtual/' + prefix + '/' + base
         self.base = base
         self.args = args
         self.reference_args = [] if references_use_default_args else args
         self.tests = {}
 
     def __repr__(self):
         return "VirtualTestSuite('%s', '%s', %s, %s)" % (self.name, self.base, self.args, self.reference_args)
 
+    def __eq__(self, other):
+        return (
+            self.name == other.name and
+            self.base == other.base and
+            self.args == other.args and
+            self.reference_args == other.reference_args)
+
 
 class PhysicalTestSuite(object):
 
     def __init__(self, base, args, reference_args=None):
         self.name = base
         self.base = base
         self.args = args
         self.reference_args = args if reference_args is None else reference_args
         self.tests = set()
 
     def __repr__(self):
         return "PhysicalTestSuite('%s', '%s', %s, %s)" % (self.name, self.base, self.args, self.reference_args)