Issue 11802: filecmp cache was growing without bound.
diff --git a/Lib/filecmp.py b/Lib/filecmp.py
index e5983cd..f5cea1d 100644
--- a/Lib/filecmp.py
+++ b/Lib/filecmp.py
@@ -48,11 +48,12 @@
if s1[1] != s2[1]:
return False
- result = _cache.get((f1, f2))
- if result and (s1, s2) == result[:2]:
- return result[2]
- outcome = _do_cmp(f1, f2)
- _cache[f1, f2] = s1, s2, outcome
+ outcome = _cache.get((f1, f2, s1, s2))
+ if outcome is None:
+ outcome = _do_cmp(f1, f2)
+ if len(_cache) > 100: # limit the maximum size of the cache
+ _cache.clear()
+ _cache[f1, f2, s1, s2] = outcome
return outcome
def _sig(st):