f53e2ef08b
* Implement checks for messages being raised with exceptions (Fixes #1080) * Add self.assertRaisesWithMessage method to relevant exercise tests - Uses self.assertRaisesRegex - Checks only for the presence of a message, not content * Add meaningful messages to failing examples * octal: Switch to using a context manager for exception tests * Add note regarding error messages to the insert * simple-linked-list: Move hints.md to correct location * simple-cipher: Remove extra whitespace from lines * collatz-conjecture: Update hints.md * Regenerate README to include exceptions section
68 lines
1.4 KiB
Python
68 lines
1.4 KiB
Python
class Node(object):
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def __init__(self, value):
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self._value = value
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self._next = None
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def value(self):
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return self._value
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def next(self):
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return self._next
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class LinkedIterator(object):
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def __init__(self, linked_list):
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self.current = linked_list._head
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def __iter__(self):
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return self
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def __next__(self):
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if self.current is None:
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raise StopIteration
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value = self.current.value()
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self.current = self.current.next()
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return value
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def next(self):
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return self.__next__()
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class LinkedList(object):
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def __init__(self, values=[]):
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self._head = None
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self._len = 0
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[self.push(v) for v in values]
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def __iter__(self):
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return LinkedIterator(self)
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def __len__(self):
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return self._len
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def head(self):
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if self._head is None:
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raise EmptyListException("The list is empty")
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return self._head
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def push(self, value):
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newNode = Node(value)
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newNode._next = self._head
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self._head = newNode
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self._len += 1
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def pop(self):
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if self._head is None:
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raise EmptyListException("The list is empty")
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self._len -= 1
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ret = self._head.value()
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self._head = self._head.next()
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return ret
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def reversed(self):
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return LinkedList(self)
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class EmptyListException(Exception):
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pass
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