unittest 基础之 —— TestResult

testresult就是存储测试结果的，不过通过何种方式调用run函数，最终到Testcase中的run方法时

必须传一个result（如果为None则自己实例化一个TestResult对象)。这个result就是TestResult

对象或者是其子类的对象，我们每次执行的结果都会调用其addFailure，addSuccess，addSkip….

等方法将执行结果保存到TestResult实例属性中。我们还是来看看TestCase的run方法：

def run(self, result=None):        orig_result = result        if result is None:#如果没有传入result对象自己实例化一个TestResult对象            result = self.defaultTestResult()            startTestRun = getattr(result, 'startTestRun', None)            if startTestRun is not None:                startTestRun()        self._resultForDoCleanups = result        result.startTest(self)        testMethod = getattr(self, self._testMethodName)        if (getattr(self.__class__, "__unittest_skip__", False) or            getattr(testMethod, "__unittest_skip__", False)):            # If the class or method was skipped.            try:                skip_why = (getattr(self.__class__, '__unittest_skip_why__', '')                            or getattr(testMethod, '__unittest_skip_why__', ''))                self._addSkip(result, skip_why)#调用addSkip            finally:                result.stopTest(self)            return        try:            success = False            try:                self.setUp()            except SkipTest as e:                self._addSkip(result, str(e))            except KeyboardInterrupt:                raise            except:                result.addError(self, sys.exc_info())#调用addError            else:                try:                    testMethod()                except KeyboardInterrupt:                    raise                except self.failureException:                    result.addFailure(self, sys.exc_info())#调用addFailure                except _ExpectedFailure as e:                    addExpectedFailure = getattr(result, 'addExpectedFailure', None)                    if addExpectedFailure is not None:                        addExpectedFailure(self, e.exc_info)#调用addExpectedFailure                    else:                        warnings.warn("TestResult has no addExpectedFailure method, reporting as passes",                                      RuntimeWarning)                        result.addSuccess(self)#调用addSuccess                except _UnexpectedSuccess:                    addUnexpectedSuccess = getattr(result, 'addUnexpectedSuccess', None)                    if addUnexpectedSuccess is not None:                        addUnexpectedSuccess(self)                    else:                        warnings.warn("TestResult has no addUnexpectedSuccess method, reporting as failures",                                      RuntimeWarning)                        result.addFailure(self, sys.exc_info())                except SkipTest as e:                    self._addSkip(result, str(e))                except:                    result.addError(self, sys.exc_info())                else:                    success = True                try:                    self.tearDown()                except KeyboardInterrupt:                    raise                except:                    result.addError(self, sys.exc_info())                    success = False            cleanUpSuccess = self.doCleanups()            success = success and cleanUpSuccess            if success:                result.addSuccess(self)        finally:            result.stopTest(self)            if orig_result is None:                stopTestRun = getattr(result, 'stopTestRun', None)                if stopTestRun is not None:                    stopTestRun()