题目
题目
单项选择题

Project01_find_06 You worked on implementing the find method in Project01. Given that the find method searches for a value in the doubly linked list (DLL) and returns the first node containing that value, what does the test case check, and why does it use self.assertIsNone(node)? # (1) find in empty DLLdll = DLL()node = dll.find(331)self.assertIsNone(node)

选项
A.It checks if the find method correctly raises an exception when searching in an empty DLL because the list is empty and should not contain any nodes.
B.It checks if the find method returns None when searching for a value in an empty DLL, because there are no nodes in the list, and therefore no node contains the value 331.
C.It checks if the find method returns a list containing None because the list is empty, and an empty list indicates that the value 331 was not found.
D.It checks if the find method returns an empty node object in an empty DLL, which is why self.assertIsNone(node) is used to validate the result.
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思路分析
Let’s unpack the scenario described in the question to understand what the test is validating. Option 1: 'It checks if the find method correctly raises an exception when searching in an empty DLL because the list is empty and should not contain any nodes.' This would be testing exception handling, but the test code uses self.assertIsNone(node), not an exception assertion. So this option misstates what the ......Login to view full explanation

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