Fix identification of venv interpreters.

testing/__init__.py

@@ -641,9 +641,13 @@ def run_pyenv(
         )
 
 
-def ensure_python_distribution(version):
-    # type: (str) -> PyenvPythonDistribution
-    if version not in ALL_PY_VERSIONS:
+def ensure_python_distribution(
+    version,  # type: str
+    python_version=None,  # type: Optional[str]
+    allow_adhoc_version=False,  # type: bool
+):
+    # type: (...) -> PyenvPythonDistribution
+    if not allow_adhoc_version and version not in ALL_PY_VERSIONS:
         raise ValueError("Please constrain version to one of {}".format(ALL_PY_VERSIONS))
 
     if WINDOWS and _ALL_PY_VERSIONS_TO_VERSION_INFO[version][:2] < (3, 8):
@@ -669,7 +673,7 @@ def ensure_python_distribution(version):
     if WINDOWS:
         python = os.path.join(interpreter_location, "python.exe")
     else:
-        major, minor = version.split(".")[:2]
+        major, minor = (python_version or version).split(".")[:2]
         python = os.path.join(
             interpreter_location, "bin", "python{major}.{minor}".format(major=major, minor=minor)
         )

tests/integration/test_issue_3113.py

@@ -0,0 +1,135 @@
+# Copyright 2026 Pex project contributors.
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+from __future__ import absolute_import
+
+import glob
+import os.path
+import shutil
+import subprocess
+from typing import Tuple
+
+import pytest
+
+from pex.common import safe_delete
+from pex.util import CacheHelper
+from testing import (
+    IS_LINUX_X86_64,
+    PyenvPythonDistribution,
+    ensure_python_distribution,
+    make_env,
+    run_pex_command,
+)
+from testing.pytest_utils.tmp import Tempdir
+
+
+@pytest.fixture
+def cowsay(tmpdir):
+    # type: (Tempdir) -> str
+
+    pex_root = tmpdir.join("pex-root")
+    cowsay = tmpdir.join("cowsay.pex")
+    run_pex_command(
+        args=[
+            "--pex-root",
+            pex_root,
+            "--runtime-pex-root",
+            pex_root,
+            "cowsay<6",
+            "-c",
+            "cowsay",
+            "-o",
+            cowsay,
+        ]
+    ).assert_success()
+    return cowsay
+
+
+def pypy_dist(
+    pyenv_version,  # type: str
+    python_version,  # type: Tuple[int, int, int]
+):
+    # type: (...) -> PyenvPythonDistribution
+    pypy_distribution = ensure_python_distribution(
+        pyenv_version,
+        python_version="{major}.{minor}".format(major=python_version[0], minor=python_version[1]),
+        allow_adhoc_version=True,
+    )
+    assert (
+        "{major}.{minor}.{patch}".format(
+            major=python_version[0], minor=python_version[1], patch=python_version[2]
+        )
+        == subprocess.check_output(
+            args=[
+                pypy_distribution.binary,
+                "-c",
+                "import sys; print('.'.join(map(str, sys.version_info[:3])))",
+            ]
+        )
+        .decode("utf-8")
+        .strip()
+    )
+    return pypy_distribution
+
+
+@pytest.fixture
+def pypy3_11_11_dist():
+    # type: () -> PyenvPythonDistribution
+    return pypy_dist("pypy3.11-7.3.19", python_version=(3, 11, 11))
+
+
+@pytest.fixture
+def pypy3_11_13_dist():
+    # type: () -> PyenvPythonDistribution
+    return pypy_dist("pypy3.11-7.3.20", python_version=(3, 11, 13))
+
+
+@pytest.mark.skipif(
+    not IS_LINUX_X86_64,
+    reason=(
+        "We only need to test this for one known-good pair of interpreters with matching binary "
+        "hash and differing patch versions. The pypy3.11-7.3.19 / pypy3.11-7.3.20 pair is known to "
+        "meet this criteria for x86_64 Linux."
+    ),
+)
+def test_interpreter_upgrade_same_binary_hash(
+    tmpdir,  # type: Tempdir
+    cowsay,  # type: str
+    pypy3_11_11_dist,  # type: PyenvPythonDistribution
+    pypy3_11_13_dist,  # type: PyenvPythonDistribution
+):
+    # type: (...) -> None
+
+    assert pypy3_11_11_dist.binary != pypy3_11_13_dist.binary
+    assert CacheHelper.hash(pypy3_11_11_dist.binary) == CacheHelper.hash(pypy3_11_13_dist.binary)
+
+    pypy_311_prefix = tmpdir.join("opt", "pypy")
+
+    def install_pypy_311_and_create_venv(
+        pypy_distribution,  # type: PyenvPythonDistribution
+        venv_dir,  # type: str
+    ):
+        # type: (...) -> str
+
+        if os.path.exists(pypy_311_prefix):
+            shutil.move(pypy_311_prefix, pypy_311_prefix + ".sav")
+        shutil.copytree(pypy_distribution.interpreter.prefix, pypy_311_prefix)
+        for binary in glob.glob(os.path.join(pypy_311_prefix, "bin", "*")):
+            if os.path.basename(binary) not in ("libpypy3.11-c.so", "pypy3.11"):
+                safe_delete(binary)
+        pypy_binary = os.path.join(pypy_311_prefix, "bin", "pypy3.11")
+        venv_path = tmpdir.join(venv_dir)
+        subprocess.check_call(args=[pypy_binary, "-m", "venv", venv_path])
+        return os.path.join(venv_path, "bin", "python")
+
+    pypy3_11_11_venv_binary = install_pypy_311_and_create_venv(pypy3_11_11_dist, "pypy3_11_11.venv")
+    assert b"| I am 3.11.11 |" in subprocess.check_output(
+        args=[pypy3_11_11_venv_binary, cowsay, "I am 3.11.11"],
+        env=make_env(PEX_PYTHON_PATH=pypy3_11_11_venv_binary),
+    )
+
+    pypy3_11_13_venv_binary = install_pypy_311_and_create_venv(pypy3_11_13_dist, "pypy3_11_13.venv")
+    assert b"| I am 3.11.13 |" in subprocess.check_output(
+        args=[pypy3_11_13_venv_binary, cowsay, "I am 3.11.13"],
+        env=make_env(PEX_PYTHON_PATH=pypy3_11_13_venv_binary),
+    )