Use dual replace to improve performance of normalize_name

[hugovk]

We can apply @henryiii's improvement to packaging in pypa/packaging#1030 (see also https://iscinumpy.dev/post/packaging-faster/) to improve the performance of normalize_name and make it ~3.4 times faster.

Benchmark

Run normalize_name(n) on every name in PyPI:

# benchmark_names_distlib.py
import sqlite3
import timeit
from distlib.util import normalize_name

# Get data with:
# curl -L https://github.com/pypi-data/pypi-json-data/releases/download/latest/pypi-data.sqlite.gz | gzip -d > pypi-data.sqlite
# Or ues pre-cached files from:
# https://gist.github.com/hugovk/efdbee0620cc64df7b405b52cf0b6e42

CACHE_FILE = "/tmp/bench/names.txt"
DB_FILE = "/tmp/bench/pypi-data.sqlite"

try:
    with open(CACHE_FILE) as f:
        TEST_ALL_NAMES = [line.rstrip("\n") for line in f]
except FileNotFoundError:
    TEST_ALL_NAMES = []
    with sqlite3.connect(DB_FILE) as conn:
        with open(CACHE_FILE, "w") as cache:
            for (name,) in conn.execute("SELECT name FROM projects"):
                if name:
                    TEST_ALL_NAMES.append(name)
                    cache.write(name + "\n")


def bench():
    for n in TEST_ALL_NAMES:
        normalize_name(n)


if __name__ == "__main__":
    print(f"Loaded {len(TEST_ALL_NAMES):,} names")
    t = timeit.timeit("bench()", globals=globals(), number=1)
    print(f"Time: {t:.4f} seconds")

Benchmark data can be found at https://gist.github.com/hugovk/efdbee0620cc64df7b405b52cf0b6e42

Before

With Python 3.14 on macOS:

❯ python benchmark_names_distlib.py
Loaded 8,344,947 names
Time: 4.6224 seconds

After

❯ python benchmark_names_distlib.py
Loaded 8,344,947 names
Time: 1.3598 seconds

3.4 times faster.

[hugovk]

Following on from pypa/packaging#1064, this is slower with 3.12 and 3.13, so marking as draft for now.

Testing on Python 3.8 to 3.14 on macOS (python.org versions) using hyperfine:

Python	master (s)	PR (s)	Result
3.8	7.699 ± 0.620	4.620 ± 0.040	PR 1.67x faster
3.9	7.463 ± 0.480	4.775 ± 0.131	PR 1.56x faster
3.10	6.042 ± 0.019	3.947 ± 0.213	PR 1.53x faster
3.11	5.437 ± 0.144	3.598 ± 0.144	PR 1.51x faster
3.12	5.707 ± 0.358	6.907 ± 0.059	⚠️ master 1.21x faster
3.13	5.248 ± 0.067	6.479 ± 0.163	⚠️ master 1.23x faster
3.14	5.784 ± 0.605	2.391 ± 0.061	PR 2.42x faster

Details

❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.8 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.8 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      7.699 s ±  0.620 s    [User: 6.703 s, System: 0.455 s]
  Range (min … max):    7.054 s …  8.290 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      4.620 s ±  0.040 s    [User: 4.381 s, System: 0.199 s]
  Range (min … max):    4.574 s …  4.650 s    3 runs

Summary
  PR ran
    1.67 ± 0.14 times faster than master

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 49s
❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.9 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.9 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      7.463 s ±  0.480 s    [User: 6.627 s, System: 0.416 s]
  Range (min … max):    7.111 s …  8.009 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      4.775 s ±  0.131 s    [User: 4.379 s, System: 0.296 s]
  Range (min … max):    4.679 s …  4.924 s    3 runs

Summary
  PR ran
    1.56 ± 0.11 times faster than master

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 50s

❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.10 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.10 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      6.042 s ±  0.019 s    [User: 5.561 s, System: 0.329 s]
  Range (min … max):    6.021 s …  6.054 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      3.947 s ±  0.213 s    [User: 3.503 s, System: 0.311 s]
  Range (min … max):    3.751 s …  4.174 s    3 runs

Summary
  PR ran
    1.53 ± 0.08 times faster than master

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 41s
❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.11 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.11 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      5.437 s ±  0.144 s    [User: 4.972 s, System: 0.274 s]
  Range (min … max):    5.279 s …  5.563 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      3.598 s ±  0.144 s    [User: 3.198 s, System: 0.265 s]
  Range (min … max):    3.463 s …  3.750 s    3 runs

Summary
  PR ran
    1.51 ± 0.07 times faster than master

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 43s
❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.12 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.12 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      5.707 s ±  0.358 s    [User: 5.005 s, System: 0.369 s]
  Range (min … max):    5.439 s …  6.113 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      6.907 s ±  0.059 s    [User: 6.439 s, System: 0.331 s]
  Range (min … max):    6.846 s …  6.963 s    3 runs

Summary
  master ran
    1.21 ± 0.08 times faster than PR

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 48s
❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.13 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.13 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      5.248 s ±  0.067 s    [User: 4.906 s, System: 0.226 s]
  Range (min … max):    5.183 s …  5.316 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      6.479 s ±  0.163 s    [User: 6.002 s, System: 0.315 s]
  Range (min … max):    6.328 s …  6.652 s    3 runs

Summary
  master ran
    1.23 ± 0.03 times faster than PR

distlib on  speedup-canonicalize_name [?] via 🐍 v3.14.2 via 💎 v3.1.3 took 31s
❯ hyperfine --warmup 1 -r 3 \
    -n master --prepare 'git checkout master' 'python3.14 benchmark_names_distlib.py' \
    -n PR --prepare 'git checkout speedup-canonicalize_name -q' 'python3.14 benchmark_names_distlib.py'
Benchmark 1: master
  Time (mean ± σ):      5.784 s ±  0.605 s    [User: 5.174 s, System: 0.275 s]
  Range (min … max):    5.370 s …  6.478 s    3 runs

Benchmark 2: PR
  Time (mean ± σ):      2.391 s ±  0.061 s    [User: 2.067 s, System: 0.223 s]
  Range (min … max):    2.321 s …  2.431 s    3 runs

Summary
  PR ran
    2.42 ± 0.26 times faster than master

[hugovk]

Updated to use the faster version from pypa/packaging#1064.

[codecov]

Codecov Report

❌ Patch coverage is 50.00000% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 81.22%. Comparing base (674a491) to head (8e613c3).
⚠️ Report is 33 commits behind head on master.

Files with missing lines	Patch %	Lines
distlib/util.py	50.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #254      +/-   ##
==========================================
- Coverage   81.49%   81.22%   -0.28%     
==========================================
  Files          24       24              
  Lines        8885     8963      +78     
  Branches     1747     1538     -209     
==========================================
+ Hits         7241     7280      +39     
- Misses       1300     1344      +44     
+ Partials      344      339       -5     

Flag	Coverage Δ
unittests	80.37% <50.00%> (-0.25%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.