This adds a new standard library module, tomllib, for parsing TOML. The recently accepted PEP 680 -- tomllib is relevant here.

This PR has already seen some review in a PR under my personal fork: hukkin#2 (thanks to @encukou, @merwok, @hauntsaninja, @JelleZijlstra (I hope I'm not forgetting anyone)).

The implementation is based on Tomli which I plan to keep maintaining as a backport for Python versions 3.7, 3.8, 3.9 and 3.10, until finally Python 3.10 goes EOL.

Steps taken (converting tomli to tomllib)

• Move everything in tomli:src/tomli to Lib/tomllib. Exclude py.typed.

• Remove __version__ = ... line from Lib/tomllib/__init__.py

• Move everything in tomli:tests to Lib/test/test_tomllib. Exclude the following test data dirs recursively:

  • tomli:tests/data/invalid/_external/
  • tomli:tests/data/valid/_external/

• Create Lib/test/test_tomllib/__main__.py:

  import unittest
  
  from . import load_tests
  
  
  unittest.main()

• Add the following to Lib/test/test_tomllib/__init__.py:

  import os
  from test.support import load_package_tests
  
  def load_tests(*args):
      return load_package_tests(os.path.dirname(__file__), *args)

  Also change import tomli as tomllib to import tomllib.

• In cpython/Lib/tomllib/_parser.py replace __fp with fp and __s with s. Add the / to load and loads function signatures.

• Run make regen-stdlib-module-names

• Create Doc/library/tomllib.rst and reference it in Doc/library/fileformats.rst

https://bugs.python.org/issue40059