Migrate stale sidecar and private uv tests to PM's current interface

tests/pm/test_workspace_output_encoding.py

@@ -9,8 +9,9 @@ import sys
 
 import pytest
 
+import pm
 import pm.workspace as ws
-from pm.package import InstallError
+from pm.package import InstallError, Runner
 
 
 @pytest.fixture
@@ -87,14 +88,35 @@ def test_node_sidecar_retains_output_and_exit_status(
     diagnostic = "🔍 node-gyp: build toolchain unavailable"
     raw = diagnostic.encode("utf-8") + b"\xff\n"
     completed = []
+    npm_dir = tmp_path / "pm-bin"
+    npm_dir.mkdir()
+    npm = npm_dir / ("npm.cmd" if os.name == "nt" else "npm")
+    npm.write_text("process boundary fixture", encoding="utf-8")
+    npm.chmod(0o755)
+    context = Runner("npm", dict(os.environ, PATH=str(npm_dir)))
+    acquisitions = []
+
+    def acquire(name, **kwargs):
+        acquisitions.append((name, kwargs))
+        return context
 
     def run_npm(cmd, **kwargs):
+        assert cmd == [str(npm), install_cmd, "--no-audit", "--no-fund"]
+        assert kwargs["env"] == context.env
+        assert kwargs["cwd"] == str(tmp_path)
+        # Keep the real Runner and decoding path; only replace npm's process
+        # with a Python child that emits controlled bytes and an exit status.
         result = legacy_locale_child(**{stream: raw}, returncode=returncode, **kwargs)
         completed.append(result)
         return result
 
-    error = ws.install_node_sidecar(tmp_path, npm_bin=sys.executable, runner=run_npm)
+    monkeypatch.setattr(pm, "ensure", acquire)
+    monkeypatch.setattr("pm.package.subprocess.run", run_npm)
+    error = ws.install_node_sidecar(tmp_path)
 
+    assert acquisitions == [("npm", {"explicit": False})]
+    assert len(completed) == 1
+    assert completed[0].returncode == returncode
     expected = diagnostic + "<EFBFBD>"
     if returncode:
         assert error == f"npm {install_cmd} exited {returncode}: {expected}"

tests/test_pm_bionic.py

@@ -174,9 +174,8 @@ def test_bionic_verify_is_file_evidence(tmp_path: Path, monkeypatch, name):
 
 
 def test_bionic_binary_and_env_contract(tmp_path: Path):
-    """On bionic, _BionicDebArm.binary() must return the staged deb's main
-    binary path (file evidence, no exec), so the base Package.env contract
-    exposes the tool through PATH like every other pm package."""
+    """Bionic binaries retain their staged paths, but only on_path packages
+    expose them in the environment; internal uv stays private to PM."""
     from pm.registry import get_package
 
     for name in ("uv", "python", "node"):
@@ -190,9 +189,12 @@ def test_bionic_binary_and_env_contract(tmp_path: Path):
         assert binary == main, f"{name}.binary() on bionic: {binary}"
 
         env = pkg.env(entry, "linux-arm64-bionic")
-        assert env.get("PATH") == [str(main.parent)], (
-            f"{name}.env() on bionic does not follow the Package.env PATH contract"
+        expected_path = [str(main.parent)] if pkg.on_path else None
+        assert env.get("PATH") == expected_path, (
+            f"{name}.env() on bionic does not follow its on_path declaration"
         )
+        if pkg.internal:
+            assert "PATH" not in env, f"internal {name} must not leak into public PATH"
 
 
 def test_stage_only_does_not_record_host_facts(tmp_path, monkeypatch):