Use uv for installing dynamic dependencies in mypy_test.py and regr_test.py (#11517)

tests/utils.py

@@ -4,13 +4,10 @@ from __future__ import annotations
 
 import os
 import re
-import subprocess
 import sys
-import venv
 from functools import lru_cache
 from pathlib import Path
 from typing import Any, Final, NamedTuple
-from typing_extensions import Annotated
 
 import pathspec
 
@@ -51,34 +48,11 @@ def print_success_msg() -> None:
 # ====================================================================
 
 
-class VenvInfo(NamedTuple):
-    pip_exe: Annotated[str, "A path to the venv's pip executable"]
-    python_exe: Annotated[str, "A path to the venv's python executable"]
-
-    @staticmethod
-    def of_existing_venv(venv_dir: Path) -> VenvInfo:
-        if sys.platform == "win32":
-            pip = venv_dir / "Scripts" / "pip.exe"
-            python = venv_dir / "Scripts" / "python.exe"
-        else:
-            pip = venv_dir / "bin" / "pip"
-            python = venv_dir / "bin" / "python"
-
-        return VenvInfo(str(pip), str(python))
-
-
-def make_venv(venv_dir: Path) -> VenvInfo:
-    try:
-        venv.create(venv_dir, with_pip=True, clear=True)
-    except subprocess.CalledProcessError as e:
-        if "ensurepip" in e.cmd and b"KeyboardInterrupt" not in e.stdout.splitlines():
-            print_error(
-                "stubtest requires a Python installation with ensurepip. "
-                "If on Linux, you may need to install the python3-venv package."
-            )
-        raise
-
-    return VenvInfo.of_existing_venv(venv_dir)
+@cache
+def venv_python(venv_dir: Path) -> Path:
+    if sys.platform == "win32":
+        return venv_dir / "Scripts" / "python.exe"
+    return venv_dir / "bin" / "python"
 
 
 @cache