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This commit is contained in:
Erik Johnston 2018-03-19 11:35:53 +00:00
parent 7c7706f42b
commit 9a0d783c11

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@ -154,11 +154,18 @@ class LruCache(object):
def cache_set(key, value, callbacks=[]):
node = cache.get(key, None)
if node is not None:
# We sometimes store large objects, e.g. dicts, which cause
# the inequality check to take a long time. So let's only do
# the check if we have some callbacks to call.
if node.callbacks and value != node.value:
for cb in node.callbacks:
cb()
node.callbacks.clear()
# We don't bother to protect this by value != node.value as
# generally size_callback will be cheap compared with equality
# checks. (For example, taking the size of two dicts is quicker
# than comparing them for equality.)
if size_callback:
cached_cache_len[0] -= size_callback(node.value)
cached_cache_len[0] += size_callback(value)