Add supported CPython/PyPy versions to cargo package metadata

Cargo.toml

@@ -41,7 +41,7 @@ hashbrown = { version = ">= 0.14.5, < 0.16", optional = true }
 indexmap = { version = ">= 2.5.0, < 3", optional = true }
 num-bigint = { version = "0.4.2", optional = true }
 num-complex = { version = ">= 0.4.6, < 0.5", optional = true }
-num-rational = {version = "0.4.1", optional = true }
+num-rational = { version = "0.4.1", optional = true }
 rust_decimal = { version = "1.15", default-features = false, optional = true }
 serde = { version = "1.0", optional = true }
 smallvec = { version = "1.0", optional = true }
@@ -63,7 +63,7 @@ rayon = "1.6.1"
 futures = "0.3.28"
 tempfile = "3.12.0"
 static_assertions = "1.1.0"
-uuid = {version = "1.10.0", features = ["v4"] }
+uuid = { version = "1.10.0", features = ["v4"] }
 
 [build-dependencies]
 pyo3-build-config = { path = "pyo3-build-config", version = "=0.23.2", features = ["resolve-config"] }
@@ -150,6 +150,14 @@ no-default-features = true
 features = ["full"]
 rustdoc-args = ["--cfg", "docsrs"]
 
+[package.metadata.cpython]
+min-version = "3.7"
+max-version = "3.13"  # inclusive
+
+[package.metadata.pypy]
+min-version = "3.9"
+max-version = "3.11"  # inclusive
+
 [workspace.lints.clippy]
 checked_conversions = "warn"
 dbg_macro = "warn"

newsfragments/4756.packaging.md

@@ -0,0 +1 @@
+Add supported CPython/PyPy versions to cargo package metadata.

noxfile.py

@@ -44,6 +44,8 @@ def test(session: nox.Session) -> None:
 
 @nox.session(name="test-rust", venv_backend="none")
 def test_rust(session: nox.Session):
+    _run_cargo_package_metadata_test(session, packages=["pyo3", "pyo3-ffi"])
+
     _run_cargo_test(session, package="pyo3-build-config")
     _run_cargo_test(session, package="pyo3-macros-backend")
     _run_cargo_test(session, package="pyo3-macros")
@@ -914,6 +916,22 @@ def _run_cargo_set_package_version(
     _run(session, *command, external=True)
 
 
+def _run_cargo_package_metadata_test(
+    session: nox.Session, *, packages: List[str]
+) -> None:
+    output = _get_output("cargo", "metadata", "--format-version=1", "--no-deps")
+    cargo_packages = json.loads(output)["packages"]
+    for package in packages:
+        # Check Python interpreter version support in package metadata
+        metadata = next(
+            pkg["metadata"] for pkg in cargo_packages if pkg["name"] == package
+        )
+        for python_impl in ["cpython", "pypy"]:
+            version_info = metadata[python_impl]
+            assert "min-version" in version_info
+            assert "max-version" in version_info
+
+
 def _get_output(*args: str) -> str:
     return subprocess.run(args, capture_output=True, text=True, check=True).stdout
 

pyo3-ffi/Cargo.toml

@@ -46,3 +46,11 @@ pyo3-build-config = { path = "../pyo3-build-config", version = "=0.23.2", featur
 
 [lints]
 workspace = true
+
+[package.metadata.cpython]
+min-version = "3.7"
+max-version = "3.13"  # inclusive
+
+[package.metadata.pypy]
+min-version = "3.9"
+max-version = "3.11"  # inclusive