1 # Copyright 2013 The Chromium Authors. All rights reserved. 2 # Use of this source code is governed by a BSD-style license that can be 3 # found in the LICENSE file. 4 5 6 class Verifier: 7 """Verifies that the current machine states match the expectation.""" 8 9 def VerifyInput(self, verifier_input, variable_expander): 10 """Verifies that the current machine states match |verifier_input|. 11 12 Args: 13 verifier_input: An input to the verifier. It is a dictionary where each 14 key is an expectation name and the associated value is an expectation 15 dictionary. The expectation dictionary may contain an optional 16 'condition' property, a string that determines whether the expectation 17 should be verified. Each subclass can specify a different expectation 18 name and expectation dictionary. 19 variable_expander: A VariableExpander object. 20 """ 21 for expectation_name, expectation in verifier_input.iteritems(): 22 if 'condition' in expectation: 23 condition = variable_expander.Expand(expectation['condition']) 24 if not self._EvaluateCondition(condition): 25 continue 26 self._VerifyExpectation(expectation_name, expectation, variable_expander) 27 28 def _VerifyExpectation(self, expectation_name, expectation, 29 variable_expander): 30 """Verifies that the current machine states match |verifier_input|. 31 32 This is an abstract method for subclasses to override. 33 34 Args: 35 expectation_name: An expectation name. Each subclass can specify a 36 different expectation name format. 37 expectation: An expectation dictionary. Each subclass can specify a 38 different expectation dictionary format. 39 variable_expander: A VariableExpander object. 40 """ 41 raise NotImplementedError() 42 43 def _EvaluateCondition(self, condition): 44 """Evaluates |condition| using eval(). 45 46 Args: 47 condition: A condition string. 48 49 Returns: 50 The result of the evaluated condition. 51 """ 52 return eval(condition, {'__builtins__': None}, None) 53
