🔧 MAINTAIN: Add a profiler tox env

MANIFEST.in

@@ -14,6 +14,7 @@ exclude .circleci
 exclude .circleci/config.yml
 exclude codecov.yml
 exclude .mypy.ini
+exclude profiler.py
 
 include LICENSE
 include LICENSE.markdown-it

profiler.py

@@ -0,0 +1,19 @@
+"""A script for profiling.
+
+To generate and read results:
+ - `tox -e profile`
+ - `firefox .tox/prof/output.svg`
+"""
+from pathlib import Path
+
+from markdown_it import MarkdownIt
+
+commonmark_spec = (
+ (Path(__file__).parent / "tests" / "test_cmark_spec" / "spec.md")
+ .read_bytes()
+ .decode()
+)
+
+# Run this a few times to emphasize over imports and other overhead above
+for _ in range(10):
+ MarkdownIt().render(commonmark_spec)

setup.cfg

@@ -70,6 +70,8 @@ benchmarking =
  psutil
  pytest
  pytest-benchmark~=3.2
+profiling =
+ gprof2dot
 
 [options.packages.find]
 exclude =

tox.ini

@@ -43,3 +43,16 @@ setenv =
 commands =
  clean: rm -rf docs/_build
  sphinx-build -nW --keep-going -b {posargs:html} docs/ docs/_build/{posargs:html}
+
+[testenv:profile]
+description = run profiler (use e.g. `firefox .tox/prof/output.svg` to open)
+extras = profiling
+allowlist_externals =
+ mkdir
+ dot
+commands =
+ mkdir -p "{toxworkdir}/prof"
+ python -m cProfile -o "{toxworkdir}/prof/output.pstats" profiler.py
+ gprof2dot -f pstats -o "{toxworkdir}/prof/output.dot" "{toxworkdir}/prof/output.pstats"
+ dot -Tsvg -o "{toxworkdir}/prof/output.svg" "{toxworkdir}/prof/output.dot"
+ python -c 'import pathlib; print("profiler svg output under file://\{0\}".format(pathlib.Path(r"{toxworkdir}") / "prof" / "output.svg"))'