mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-03 16:39:00 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

bpo-30040: new empty dict uses key-sharing dict (GH-1080)

Browse source 
Sizeof new empty dict becomes 72 bytes from 240 bytes (amd64).
It is same size to empty dict created by dict.clear().
This commit is contained in:
Inada Naoki 2019-03-12 17:25:44 +09:00 • committed by GitHub
parent fc06a192fd
commit f2a186712b
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
4 changed files with 13 additions and 8 deletions
Download patch file Download diff file Expand all files Collapse all files

6
Lib/test/test_descr.py
View file

@ -5346,16 +5346,16 @@ class SharedKeyTests(unittest.TestCase):
a, b = A(), B()
self.assertEqual(sys.getsizeof(vars(a)), sys.getsizeof(vars(b)))
self.assertLess(sys.getsizeof(vars(a)), sys.getsizeof({}))
self.assertLess(sys.getsizeof(vars(a)), sys.getsizeof({"a":1}))
# Initial hash table can contain at most 5 elements.
# Set 6 attributes to cause internal resizing.
a.x, a.y, a.z, a.w, a.v, a.u = range(6)
self.assertNotEqual(sys.getsizeof(vars(a)), sys.getsizeof(vars(b)))
a2 = A()
self.assertEqual(sys.getsizeof(vars(a)), sys.getsizeof(vars(a2)))
self.assertLess(sys.getsizeof(vars(a)), sys.getsizeof({}))
self.assertLess(sys.getsizeof(vars(a)), sys.getsizeof({"a":1}))
b.u, b.v, b.w, b.t, b.s, b.r = range(6)
self.assertLess(sys.getsizeof(vars(b)), sys.getsizeof({}))
self.assertLess(sys.getsizeof(vars(b)), sys.getsizeof({"a":1}))
class DebugHelperMeta(type):