Add a new script to generate builtin module names (#12696)

scripts/generate_builtin_modules.py

@@ -0,0 +1,116 @@
+"""Script to generate `crates/ruff_python_stdlib/src/builtin_modules.rs`.
+
+This script requires the following executables to be callable via a subprocess:
+- `python3.7`
+- `python3.8`
+- `python3.9`
+- `python3.10`
+- `python3.11`
+- `python3.12`
+- `python3.13`
+"""
+
+from __future__ import annotations
+
+import builtins
+import subprocess
+import textwrap
+from functools import partial
+from pathlib import Path
+
+MODULE_CRATE = "ruff_python_stdlib"
+MODULE_PATH = Path("crates") / MODULE_CRATE / "src" / "sys" / "builtin_modules.rs"
+
+type Version = tuple[int, int]
+
+PYTHON_VERSIONS: list[Version] = [
+    (3, 7),
+    (3, 8),
+    (3, 9),
+    (3, 10),
+    (3, 11),
+    (3, 12),
+    (3, 13),
+]
+
+
+def builtin_modules_on_version(major_version: int, minor_version: int) -> set[str]:
+    executable = f"python{major_version}.{minor_version}"
+    try:
+        proc = subprocess.run(
+            [executable, "-c", "import sys; print(sys.builtin_module_names)"],
+            check=True,
+            text=True,
+            capture_output=True,
+        )
+    except subprocess.CalledProcessError as e:
+        print(e.stdout)
+        print(e.stderr)
+        raise
+    return set(eval(proc.stdout))
+
+
+def generate_module(
+    script_destination: Path, crate_name: str, python_versions: list[Version]
+) -> None:
+    with script_destination.open("w") as f:
+        print = partial(builtins.print, file=f)
+
+        print(
+            textwrap.dedent(
+                """\
+                //! This file is generated by `scripts/generate_builtin_modules.py`
+
+                /// Return `true` if `module` is a [builtin module] on the given
+                /// Python 3 version.
+                ///
+                /// "Builtin modules" are modules that are compiled directly into the
+                /// Python interpreter. These can never be shadowed by first-party
+                /// modules; the normal rules of module resolution do not apply to these
+                /// modules.
+                ///
+                /// [builtin module]: https://docs.python.org/3/library/sys.html#sys.builtin_module_names
+                #[allow(clippy::unnested_or_patterns)]
+                pub fn is_builtin_module(minor_version: u8, module: &str) -> bool {
+                    matches!((minor_version, module),
+                """,
+            )
+        )
+
+        modules_by_version = {
+            minor_version: builtin_modules_on_version(major_version, minor_version)
+            for major_version, minor_version in python_versions
+        }
+
+        # First, add a case for the modules that are in all versions.
+        ubiquitous_modules = set.intersection(*modules_by_version.values())
+
+        print("(_, ")
+        for i, module in enumerate(sorted(ubiquitous_modules)):
+            if i > 0:
+                print(" | ", end="")
+            print(f'"{module}"')
+        print(")")
+
+        # Next, add any version-specific modules.
+        for _major_version, minor_version in python_versions:
+            version_modules = set.difference(
+                modules_by_version[minor_version],
+                ubiquitous_modules,
+            )
+
+            print(" | ")
+            print(f"({minor_version}, ")
+            for i, module in enumerate(sorted(version_modules)):
+                if i > 0:
+                    print(" | ", end="")
+                print(f'"{module}"')
+            print(")")
+
+        print(")}")
+
+    subprocess.run(["cargo", "fmt", "--package", crate_name], check=True)
+
+
+if __name__ == "__main__":
+    generate_module(MODULE_PATH, MODULE_CRATE, PYTHON_VERSIONS)