cpython/Lib/test/test_zipfile/_path/test_complexity.py

108 lines
3.2 KiB
Python

import io
import itertools
import math
import re
import string
import unittest
import zipfile
from ._functools import compose
from ._itertools import consume
from ._support import import_or_skip
big_o = import_or_skip('big_o')
pytest = import_or_skip('pytest')
class TestComplexity(unittest.TestCase):
@pytest.mark.flaky
def test_implied_dirs_performance(self):
best, others = big_o.big_o(
compose(consume, zipfile._path.CompleteDirs._implied_dirs),
lambda size: [
'/'.join(string.ascii_lowercase + str(n)) for n in range(size)
],
max_n=1000,
min_n=1,
)
assert best <= big_o.complexities.Linear
def make_zip_path(self, depth=1, width=1) -> zipfile.Path:
"""
Construct a Path with width files at every level of depth.
"""
zf = zipfile.ZipFile(io.BytesIO(), mode='w')
pairs = itertools.product(self.make_deep_paths(depth), self.make_names(width))
for path, name in pairs:
zf.writestr(f"{path}{name}.txt", b'')
zf.filename = "big un.zip"
return zipfile.Path(zf)
@classmethod
def make_names(cls, width, letters=string.ascii_lowercase):
"""
>>> list(TestComplexity.make_names(1))
['a']
>>> list(TestComplexity.make_names(2))
['a', 'b']
>>> list(TestComplexity.make_names(30))
['aa', 'ab', ..., 'bd']
>>> list(TestComplexity.make_names(17124))
['aaa', 'aab', ..., 'zip']
"""
# determine how many products are needed to produce width
n_products = max(1, math.ceil(math.log(width, len(letters))))
inputs = (letters,) * n_products
combinations = itertools.product(*inputs)
names = map(''.join, combinations)
return itertools.islice(names, width)
@classmethod
def make_deep_paths(cls, depth):
return map(cls.make_deep_path, range(depth))
@classmethod
def make_deep_path(cls, depth):
return ''.join(('d/',) * depth)
def test_baseline_regex_complexity(self):
best, others = big_o.big_o(
lambda path: re.fullmatch(r'[^/]*\\.txt', path),
self.make_deep_path,
max_n=100,
min_n=1,
)
assert best <= big_o.complexities.Constant
@pytest.mark.flaky
def test_glob_depth(self):
best, others = big_o.big_o(
lambda path: consume(path.glob('*.txt')),
self.make_zip_path,
max_n=100,
min_n=1,
)
assert best <= big_o.complexities.Linear
@pytest.mark.flaky
def test_glob_width(self):
best, others = big_o.big_o(
lambda path: consume(path.glob('*.txt')),
lambda size: self.make_zip_path(width=size),
max_n=100,
min_n=1,
)
assert best <= big_o.complexities.Linear
@pytest.mark.flaky
def test_glob_width_and_depth(self):
best, others = big_o.big_o(
lambda path: consume(path.glob('*.txt')),
lambda size: self.make_zip_path(depth=size, width=size),
max_n=10,
min_n=1,
)
assert best <= big_o.complexities.Linear