Remove venv for stubtest stdlib (#10259)

Author: hauntsaninja

stdlib/distutils/__init__.pyi

@@ -0,0 +1,5 @@
+# Attempts to improve these stubs are probably not the best use of time:
+# - distutils is deleted in Python 3.12 and newer
+# - Most users already do not use stdlib distutils, due to setuptools monkeypatching
+# - We have very little quality assurance on these stubs, since due to the two above issues
+#   we allowlist all distutils errors in stubtest.

tests/stubtest_stdlib.py

@@ -10,79 +10,56 @@
 
 import subprocess
 import sys
-import tempfile
 from pathlib import Path
 
-from utils import get_mypy_req, make_venv, print_error
-
 
 def run_stubtest(typeshed_dir: Path) -> int:
     allowlist_dir = typeshed_dir / "tests" / "stubtest_allowlists"
     version_allowlist = f"py{sys.version_info.major}{sys.version_info.minor}.txt"
     platform_allowlist = f"{sys.platform}.txt"
     combined_allowlist = f"{sys.platform}-py{sys.version_info.major}{sys.version_info.minor}.txt"
-    with tempfile.TemporaryDirectory() as tmp:
-        venv_dir = Path(tmp)
-        print("Setting up an isolated virtual environment...", file=sys.stderr)
-        try:
-            pip_exe, python_exe = make_venv(venv_dir)
-        except Exception:
-            print_error("fail")
-            raise
-
-        # Install the same mypy version as in "requirements-tests.txt"
-        try:
-            install_command = [pip_exe, "install", get_mypy_req()]
-            subprocess.run(install_command, check=True, text=True, capture_output=True)
-        except subprocess.CalledProcessError as e:
-            print(e.stderr, file=sys.stderr)
-            raise
-
-        # Uninstall setuptools from the venv so we can test stdlib's distutils
-        try:
-            uninstall_command = [pip_exe, "uninstall", "-y", "setuptools"]
-            subprocess.run(uninstall_command, check=True, text=True, capture_output=True)
-        except subprocess.CalledProcessError as e:
-            print(e.stderr, file=sys.stderr)
-            raise
 
-        cmd = [
-            python_exe,
-            "-m",
-            "mypy.stubtest",
-            "--check-typeshed",
-            "--custom-typeshed-dir",
-            str(typeshed_dir),
-            "--allowlist",
-            str(allowlist_dir / "py3_common.txt"),
-            "--allowlist",
-            str(allowlist_dir / version_allowlist),
-        ]
-        if (allowlist_dir / platform_allowlist).exists():
-            cmd += ["--allowlist", str(allowlist_dir / platform_allowlist)]
-        if (allowlist_dir / combined_allowlist).exists():
-            cmd += ["--allowlist", str(allowlist_dir / combined_allowlist)]
-        if sys.version_info < (3, 10):
-            # As discussed in https://github.com/python/typeshed/issues/3693, we only aim for
-            # positional-only arg accuracy for python 3.10 and above.
-            cmd += ["--ignore-positional-only"]
-        print(" ".join(cmd), file=sys.stderr)
-        try:
-            subprocess.run(cmd, check=True)
-        except subprocess.CalledProcessError as e:
-            print(
-                "\nNB: stubtest output depends on the Python version (and system) it is run with. "
-                + "See README.md for more details.\n"
-                + "NB: We only check positional-only arg accuracy for Python 3.10.\n"
-                + f"\nCommand run was: {' '.join(cmd)}\n",
-                file=sys.stderr,
-            )
-            print("\n\n", file=sys.stderr)
-            print(f'To fix "unused allowlist" errors, remove the corresponding entries from {allowlist_dir}', file=sys.stderr)
-            return e.returncode
-        else:
-            print("stubtest succeeded", file=sys.stderr)
-            return 0
+    # Note when stubtest imports distutils, it will likely actually import setuptools._distutils
+    # This is fine because we don't care about distutils and allowlist all errors from it
+    # https://github.com/python/typeshed/pull/10253#discussion_r1216712404
+    # https://github.com/python/typeshed/pull/9734
+    cmd = [
+        sys.executable,
+        "-m",
+        "mypy.stubtest",
+        "--check-typeshed",
+        "--custom-typeshed-dir",
+        str(typeshed_dir),
+        "--allowlist",
+        str(allowlist_dir / "py3_common.txt"),
+        "--allowlist",
+        str(allowlist_dir / version_allowlist),
+    ]
+    if (allowlist_dir / platform_allowlist).exists():
+        cmd += ["--allowlist", str(allowlist_dir / platform_allowlist)]
+    if (allowlist_dir / combined_allowlist).exists():
+        cmd += ["--allowlist", str(allowlist_dir / combined_allowlist)]
+    if sys.version_info < (3, 10):
+        # As discussed in https://github.com/python/typeshed/issues/3693, we only aim for
+        # positional-only arg accuracy for python 3.10 and above.
+        cmd += ["--ignore-positional-only"]
+    print(" ".join(cmd), file=sys.stderr)
+    try:
+        subprocess.run(cmd, check=True)
+    except subprocess.CalledProcessError as e:
+        print(
+            "\nNB: stubtest output depends on the Python version (and system) it is run with. "
+            + "See README.md for more details.\n"
+            + "NB: We only check positional-only arg accuracy for Python 3.10.\n"
+            + f"\nCommand run was: {' '.join(cmd)}\n",
+            file=sys.stderr,
+        )
+        print("\n\n", file=sys.stderr)
+        print(f'To fix "unused allowlist" errors, remove the corresponding entries from {allowlist_dir}', file=sys.stderr)
+        return e.returncode
+    else:
+        print("stubtest succeeded", file=sys.stderr)
+        return 0
 
 
 if __name__ == "__main__":