replace dangerous monkeypatch with mocker.patch

src/pipdeptree/_discovery.py

@@ -34,8 +34,8 @@ def get_installed_distributions(
             cmd = "import sys; print(sys.path)"
 
         args = [str(py_path), "-c", cmd]
-        result = subprocess.run(args, stdout=subprocess.PIPE, check=False)  # noqa: S603
-        original_dists = distributions(path=ast.literal_eval(result.stdout.decode("utf-8")))
+        result = subprocess.run(args, stdout=subprocess.PIPE, check=False, text=True)  # noqa: S603
+        original_dists = distributions(path=ast.literal_eval(result.stdout))
     elif local_only and in_venv:
         venv_site_packages = [p for p in sys.path if p.startswith(sys.prefix)]
         original_dists = distributions(path=venv_site_packages)

tests/_models/test_package.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import sys
 from importlib.metadata import PackageNotFoundError
 from pathlib import Path
 from typing import TYPE_CHECKING, Any
@@ -26,11 +27,13 @@ def test_guess_version_setuptools(mocker: MockerFixture) -> None:
     assert result == "?"
 
 
-def test_package_as_frozen_repr(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+def test_package_as_frozen_repr(tmp_path: Path, mocker: MockerFixture) -> None:
     file_path = tmp_path / "foo.egg-link"
     with Path(file_path).open("w") as f:
         f.write("/A/B/foo")
-    monkeypatch.syspath_prepend(str(tmp_path))
+    mock_path = sys.path.copy()
+    mock_path.append(str(tmp_path))
+    mocker.patch("pipdeptree._discovery.sys.path", mock_path)
     json_text = '{"dir_info": {"editable": true}}'
     foo = Mock(metadata={"Name": "foo"}, version="20.4.1")
     foo.read_text = Mock(return_value=json_text)

tests/test_discovery.py

@@ -16,7 +16,7 @@
     from pytest_mock import MockerFixture
 
 
-def test_local_only(tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capfd: pytest.CaptureFixture[str]) -> None:
+def test_local_only(tmp_path: Path, mocker: MockerFixture, capfd: pytest.CaptureFixture[str]) -> None:
     venv_path = str(tmp_path / "venv")
     result = virtualenv.cli_run([venv_path, "--activators", ""])
     venv_site_packages = site.getsitepackages([venv_path])
@@ -27,10 +27,11 @@ def test_local_only(tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capfd: pyte
         f.write("Metadata-Version: 2.3\n" "Name: foo\n" "Version: 1.2.5\n")
 
     cmd = [str(result.creator.exe.parent / "python3"), "--local-only"]
-    monkeypatch.setattr(sys, "prefix", venv_path)
-    for s in venv_site_packages:
-        monkeypatch.syspath_prepend(s)
-    monkeypatch.setattr(sys, "argv", cmd)
+    mocker.patch("pipdeptree._discovery.sys.prefix", venv_path)
+    sys_path = sys.path.copy()
+    mock_path = sys_path + venv_site_packages
+    mocker.patch("pipdeptree._discovery.sys.path", mock_path)
+    mocker.patch("pipdeptree._discovery.sys.argv", cmd)
     main()
     out, _ = capfd.readouterr()
     found = {i.split("==")[0] for i in out.splitlines()}
@@ -41,16 +42,16 @@ def test_local_only(tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capfd: pyte
     assert found == expected
 
 
-def test_user_only(tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capfd: pytest.CaptureFixture[str]) -> None:
+def test_user_only(tmp_path: Path, mocker: MockerFixture, capfd: pytest.CaptureFixture[str]) -> None:
     fake_dist = Path(tmp_path) / "foo-1.2.5.dist-info"
     fake_dist.mkdir()
     fake_metadata = Path(fake_dist) / "METADATA"
     with Path(fake_metadata).open("w") as f:
         f.write("Metadata-Version: 2.3\n" "Name: foo\n" "Version: 1.2.5\n")
 
-    monkeypatch.setattr(site, "getusersitepackages", Mock(return_value=str(tmp_path)))
     cmd = [sys.executable, "--user-only"]
-    monkeypatch.setattr(sys, "argv", cmd)
+    mocker.patch("pipdeptree._discovery.site.getusersitepackages", Mock(return_value=str(tmp_path)))
+    mocker.patch("pipdeptree._discovery.sys.argv", cmd)
     main()
     out, _ = capfd.readouterr()
     found = {i.split("==")[0] for i in out.splitlines()}

tests/test_non_host.py

@@ -12,10 +12,13 @@
 if TYPE_CHECKING:
     from pathlib import Path
 
+    from pytest_mock import MockerFixture
+
 
 @pytest.mark.parametrize("args_joined", [True, False])
 def test_custom_interpreter(
     tmp_path: Path,
+    mocker: MockerFixture,
     monkeypatch: pytest.MonkeyPatch,
     capfd: pytest.CaptureFixture[str],
     args_joined: bool,
@@ -25,7 +28,7 @@ def test_custom_interpreter(
     monkeypatch.chdir(tmp_path)
     py = str(result.creator.exe.relative_to(tmp_path))
     cmd += [f"--python={result.creator.exe}"] if args_joined else ["--python", py]
-    monkeypatch.setattr(sys, "argv", cmd)
+    mocker.patch("pipdeptree._discovery.sys.argv", cmd)
     main()
     out, _ = capfd.readouterr()
     found = {i.split("==")[0] for i in out.splitlines()}
@@ -43,16 +46,16 @@ def test_custom_interpreter(
 
 def test_custom_interpreter_with_local_only(
     tmp_path: Path,
-    monkeypatch: pytest.MonkeyPatch,
+    mocker: MockerFixture,
     capfd: pytest.CaptureFixture[str],
 ) -> None:
     venv_path = str(tmp_path / "venv")
 
     result = virtualenv.cli_run([venv_path, "--system-site-packages", "--activators", ""])
 
     cmd = ["", f"--python={result.creator.exe}", "--local-only"]
-    monkeypatch.setattr(sys, "prefix", venv_path)
-    monkeypatch.setattr(sys, "argv", cmd)
+    mocker.patch("pipdeptree._discovery.sys.prefix", venv_path)
+    mocker.patch("pipdeptree._discovery.sys.argv", cmd)
     main()
     out, _ = capfd.readouterr()
     found = {i.split("==")[0] for i in out.splitlines()}