Fix release.py test-release smoke test for new release style (Cherr…

…y-pick of #20002) (#20073)

This adjusts the `test-release` subcommand of the `release.py` script to
do a smoke test that works with the new release style. This is step 4 of
the release procedure, and is, in my mind, designed to catch major infra
failures. For instance, if things haven't been published at all.

Co-authored-by: Huon Wilson <huon@exoflare.io>

src/python/pants_release/release.py

@@ -487,6 +487,15 @@ def build_all_wheels() -> None:
     )
 
 
+def install_and_test_packages(version: str, *, extra_pip_args: list[str] | None = None) -> None:
+    with create_tmp_venv() as bin_dir:
+        for pkg in PACKAGES:
+            pip_req = f"{pkg.name}=={version}"
+            banner(f"Installing and testing {pip_req}")
+            pkg.validate(version, bin_dir, extra_pip_args or [])
+            green(f"Tests succeeded for {pip_req}")
+
+
 def build_pants_wheels() -> None:
     banner(f"Building Pants wheels with Python {CONSTANTS.python_version}")
     version = CONSTANTS.pants_stable_version
@@ -809,17 +818,63 @@ def prompt_to_generate_docs() -> None:
 
 def test_release() -> None:
     banner("Installing and testing the latest released packages")
-    install_and_test_packages(CONSTANTS.pants_stable_version)
-    banner("Successfully installed and tested the latest released packages")
+    smoke_test_install_and_version(CONSTANTS.pants_stable_version)
+    banner("Successfully ran a smoke test of the released packages")
+
+
+def smoke_test_install_and_version(version: str) -> None:
+    """Do two tests to confirm that both sets of artifacts (PEXes for running normally, and wheels
+    for plugins) have ended up somewhere plausible, to catch major infra failures."""
+    with temporary_dir() as dir_:
+        dir = Path(dir_)
+        (dir / "pants.toml").write_text(
+            f"""
+            [GLOBAL]
+            pants_version = "{version}"
+
+            backend_packages = [
+                "pants.backend.python",
+                "pants.backend.plugin_development",
+            ]
 
+            [python]
+            interpreter_constraints = ["==3.9.*"]
+            enable_resolves = true
+            """
+        )
 
-def install_and_test_packages(version: str, *, extra_pip_args: list[str] | None = None) -> None:
-    with create_tmp_venv() as bin_dir:
-        for pkg in PACKAGES:
-            pip_req = f"{pkg.name}=={version}"
-            banner(f"Installing and testing {pip_req}")
-            pkg.validate(version, bin_dir, extra_pip_args or [])
-            green(f"Tests succeeded for {pip_req}")
+        # First: test that running pants normally reports the expected version:
+        result = subprocess.run(
+            ["pants", "version"],
+            cwd=dir,
+            check=True,
+            stdout=subprocess.PIPE,
+        )
+        printed_version = result.stdout.decode().strip()
+        if printed_version != version:
+            die(f"Failed to confirm pants version, expected {version!r}, got {printed_version!r}")
+
+        # Second: test that the wheels can be installed/imported (for plugins):
+        (dir / "BUILD").write_text("python_sources(name='py'); pants_requirements(name='pants')")
+        # We confirm the version from the main wheel, but only check that the testutil code can
+        # be imported at all.
+        (dir / "example.py").write_text(
+            "from pants import version, testutil; print(version.VERSION)"
+        )
+        result = subprocess.run(
+            ["pants", "generate-lockfiles"],
+            cwd=dir,
+            check=True,
+        )
+        result = subprocess.run(
+            ["pants", "run", "example.py"],
+            cwd=dir,
+            check=True,
+            stdout=subprocess.PIPE,
+        )
+        wheel_version = result.stdout.decode().strip()
+        if printed_version != version:
+            die(f"Failed to confirm wheel version, expected {version!r}, got {wheel_version!r}")
 
 
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