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-rw-r--r--Tools/Scripts/webkitpy/common/lru_cache.py134
1 files changed, 0 insertions, 134 deletions
diff --git a/Tools/Scripts/webkitpy/common/lru_cache.py b/Tools/Scripts/webkitpy/common/lru_cache.py
deleted file mode 100644
index 02a3d1c35..000000000
--- a/Tools/Scripts/webkitpy/common/lru_cache.py
+++ /dev/null
@@ -1,134 +0,0 @@
-# Copyright (C) 2011 Google Inc. All rights reserved.
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
-#
-# * Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-# * Redistributions in binary form must reproduce the above
-# copyright notice, this list of conditions and the following disclaimer
-# in the documentation and/or other materials provided with the
-# distribution.
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-
-class Node():
- def __init__(self, key, value):
- self.key = key
- self.value = value
- self.prev = None
- self.next = None
-
-
-class LRUCache():
- """An implementation of Least Recently Used (LRU) Cache."""
-
- def __init__(self, capacity):
- """Initializes a lru cache with the given capacity.
-
- Args:
- capacity: The capacity of the cache.
- """
- assert capacity > 0, "capacity (%s) must be greater than zero." % capacity
- self._first = None
- self._last = None
- self._dict = {}
- self._capacity = capacity
-
- def __setitem__(self, key, value):
- if key in self._dict:
- self.__delitem__(key)
- if not self._first:
- self._one_node(key, value)
- return
- if len(self._dict) >= self._capacity:
- del self._dict[self._last.key]
- if self._capacity == 1:
- self._one_node(key, value)
- return
- self._last = self._last.next
- self._last.prev = None
- node = Node(key, value)
- node.prev = self._first
- self._first.next = node
- self._first = node
- self._dict[key] = node
-
- def _one_node(self, key, value):
- node = Node(key, value)
- self._dict[key] = node
- self._first = node
- self._last = node
-
- def __getitem__(self, key):
- if not self._first:
- raise KeyError(str(key))
- if self._first.key == key:
- return self._first.value
-
- if self._last.key == key:
- next_last = self._last.next
- next_last.prev = None
- next_first = self._last
- next_first.prev = self._first
- next_first.next = None
- self._first.next = next_first
- self._first = next_first
- self._last = next_last
- return self._first.value
-
- node = self._dict[key]
- node.next.prev = node.prev
- node.prev.next = node.next
- node.prev = self._first
- node.next = None
- self._first.next = node
- self._first = node
- return self._first.value
-
- def __delitem__(self, key):
- node = self._dict[key]
- del self._dict[key]
- if self._first is self._last:
- self._last = None
- self._first = None
- return
- if self._first is node:
- self._first = node.prev
- self._first.next = None
- return
- if self._last is node:
- self._last = node.next
- self._last.prev = None
- return
- node.next.prev = node.prev
- node.prev.next = node.next
-
- def __len__(self):
- return len(self._dict)
-
- def __contains__(self, key):
- return key in self._dict
-
- def __iter__(self):
- return iter(self._dict)
-
- def items(self):
- return [(key, node.value) for key, node in self._dict.items()]
-
- def values(self):
- return [node.value for node in self._dict.values()]
-
- def keys(self):
- return self._dict.keys()