diff --git a/archive.py b/archive.py index fcecae7f..5a2d6d10 100755 --- a/archive.py +++ b/archive.py @@ -118,7 +118,7 @@ if __name__ == '__main__': write_links_index(archive_path, links) # Step 3: Verify folder structure is 1:1 with index - cleanup_archive(archive_path, links) + # cleanup_archive(archive_path, links) # Step 4: Run the archive methods for each link update_archive(archive_path, links, source=source, resume=resume, append=True) diff --git a/peekable.py b/peekable.py new file mode 100644 index 00000000..cd952f5e --- /dev/null +++ b/peekable.py @@ -0,0 +1,109 @@ +from collections import deque + +_marker = object() + +class Peekable(object): + def __init__(self, iterable): + self._it = iter(iterable) + self._cache = deque() + + def __iter__(self): + return self + + def __bool__(self): + try: + self.peek() + except StopIteration: + return False + return True + + def __nonzero__(self): + # For Python 2 compatibility + return self.__bool__() + + def peek(self, default=_marker): + """Return the item that will be next returned from ``next()``. + Return ``default`` if there are no items left. If ``default`` is not + provided, raise ``StopIteration``. + """ + if not self._cache: + try: + self._cache.append(next(self._it)) + except StopIteration: + if default is _marker: + raise + return default + return self._cache[0] + + def prepend(self, *items): + """Stack up items to be the next ones returned from ``next()`` or + ``self.peek()``. The items will be returned in + first in, first out order:: + >>> p = peekable([1, 2, 3]) + >>> p.prepend(10, 11, 12) + >>> next(p) + 10 + >>> list(p) + [11, 12, 1, 2, 3] + It is possible, by prepending items, to "resurrect" a peekable that + previously raised ``StopIteration``. + >>> p = peekable([]) + >>> next(p) + Traceback (most recent call last): + ... + StopIteration + >>> p.prepend(1) + >>> next(p) + 1 + >>> next(p) + Traceback (most recent call last): + ... + StopIteration + """ + self._cache.extendleft(reversed(items)) + + def __next__(self): + if self._cache: + return self._cache.popleft() + + return next(self._it) + + next = __next__ # For Python 2 compatibility + + def _get_slice(self, index): + # Normalize the slice's arguments + step = 1 if (index.step is None) else index.step + if step > 0: + start = 0 if (index.start is None) else index.start + stop = maxsize if (index.stop is None) else index.stop + elif step < 0: + start = -1 if (index.start is None) else index.start + stop = (-maxsize - 1) if (index.stop is None) else index.stop + else: + raise ValueError('slice step cannot be zero') + + # If either the start or stop index is negative, we'll need to cache + # the rest of the iterable in order to slice from the right side. + if (start < 0) or (stop < 0): + self._cache.extend(self._it) + # Otherwise we'll need to find the rightmost index and cache to that + # point. + else: + n = min(max(start, stop) + 1, maxsize) + cache_len = len(self._cache) + if n >= cache_len: + self._cache.extend(islice(self._it, n - cache_len)) + + return list(self._cache)[index] + + def __getitem__(self, index): + if isinstance(index, slice): + return self._get_slice(index) + + cache_len = len(self._cache) + if index < 0: + self._cache.extend(self._it) + elif index >= cache_len: + self._cache.extend(islice(self._it, index + 1 - cache_len)) + + return self._cache[index]