chore: move metadata to pyproject.toml (#245)

Assisted-by: ClaudeCode:claude-opus-5-5

Author: henryiii

pyproject.toml

@@ -1,10 +1,23 @@
 [build-system]
 requires = [
-    "setuptools>=42",
+    "setuptools>=61",
     "pybind11>=2.10.0",
 ]
 build-backend = "setuptools.build_meta"
 
+[project]
+name = "python_example"
+version = "0.0.1"
+description = "A test project using pybind11"
+authors = [{ name = "Sylvain Corlay", email = "sylvain.corlay@gmail.com" }]
+requires-python = ">=3.11"
+
+[project.urls]
+Homepage = "https://github.com/pybind/python_example"
+
+[project.optional-dependencies]
+test = ["pytest"]
+
 
 [tool.cibuildwheel]
 test-command = "python {project}/tests/test.py"

setup.py

@@ -1,8 +1,12 @@
 # Available at setup time due to pyproject.toml
+import tomllib
+from pathlib import Path
+
 from pybind11.setup_helpers import Pybind11Extension, build_ext
 from setuptools import setup
 
-__version__ = "0.0.1"
+with Path(__file__).with_name("pyproject.toml").open("rb") as f:
+    __version__ = tomllib.load(f)["project"]["version"]
 
 # The main interface is through Pybind11Extension.
 # * You can add cxx_std=11/14/17, and then build_ext can be removed.
@@ -23,18 +27,8 @@
 ]
 
 setup(
-    name="python_example",
-    version=__version__,
-    author="Sylvain Corlay",
-    author_email="sylvain.corlay@gmail.com",
-    url="https://github.com/pybind/python_example",
-    description="A test project using pybind11",
-    long_description="",
     ext_modules=ext_modules,
-    extras_require={"test": "pytest"},
     # Currently, build_ext only provides an optional "highest supported C++
     # level" feature, but in the future it may provide more features.
     cmdclass={"build_ext": build_ext},
-    zip_safe=False,
-    python_requires=">=3.11",
 )