Add an option to the test suite to specify a zipapp to test

Author: pfmoore

tests/conftest.py

@@ -84,6 +84,12 @@ def pytest_addoption(parser: Parser) -> None:
         default=None,
         help="use given proxy in session network tests",
     )
+    parser.addoption(
+        "--use-zipapp",
+        action="store",
+        default=None,
+        help="use given pip zipapp when running pip in tests",
+    )
 
 
 def pytest_collection_modifyitems(config: Config, items: List[pytest.Function]) -> None:
@@ -487,7 +493,7 @@ def with_wheel(virtualenv: VirtualEnvironment, wheel_install: Path) -> None:
 
 class ScriptFactory(Protocol):
     def __call__(
-        self, tmpdir: Path, virtualenv: Optional[VirtualEnvironment] = None
+        self, tmpdir: Path, virtualenv: Optional[VirtualEnvironment] = None, zipapp: Optional[str] = None
     ) -> PipTestEnvironment:
         ...
 
@@ -497,7 +503,7 @@ def script_factory(
     virtualenv_factory: Callable[[Path], VirtualEnvironment], deprecated_python: bool
 ) -> ScriptFactory:
     def factory(
-        tmpdir: Path, virtualenv: Optional[VirtualEnvironment] = None
+        tmpdir: Path, virtualenv: Optional[VirtualEnvironment] = None, zipapp: Optional[str] = None,
     ) -> PipTestEnvironment:
         if virtualenv is None:
             virtualenv = virtualenv_factory(tmpdir.joinpath("venv"))
@@ -516,13 +522,16 @@ def factory(
             assert_no_temp=True,
             # Deprecated python versions produce an extra deprecation warning
             pip_expect_warning=deprecated_python,
+            # Tell the Test Environment if we want to run pip via a zipapp
+            zipapp=zipapp,
         )
 
     return factory
 
 
 @pytest.fixture
 def script(
+    request: pytest.FixtureRequest,
     tmpdir: Path,
     virtualenv: VirtualEnvironment,
     script_factory: ScriptFactory,
@@ -533,7 +542,8 @@ def script(
     test function. The returned object is a
     ``tests.lib.PipTestEnvironment``.
     """
-    return script_factory(tmpdir.joinpath("workspace"), virtualenv)
+    zipapp = request.config.getoption("--use-zipapp")
+    return script_factory(tmpdir.joinpath("workspace"), virtualenv, zipapp)
 
 
 @pytest.fixture(scope="session")

tests/lib/__init__.py

@@ -507,6 +507,7 @@ def __init__(
         *args: Any,
         virtualenv: VirtualEnvironment,
         pip_expect_warning: bool = False,
+        zipapp: Optional[str] = None,
         **kwargs: Any,
     ) -> None:
         # Store paths related to the virtual environment
@@ -553,6 +554,9 @@ def __init__(
         # (useful for Python version deprecation)
         self.pip_expect_warning = pip_expect_warning
 
+        # The name of an (optional) zipapp to use when running pip
+        self.zipapp = zipapp
+
         # Call the TestFileEnvironment __init__
         super().__init__(base_path, *args, **kwargs)
 
@@ -698,7 +702,10 @@ def pip(
         __tracebackhide__ = True
         if self.pip_expect_warning:
             kwargs["allow_stderr_warning"] = True
-        if use_module:
+        if self.zipapp:
+            exe = "python"
+            args = (self.zipapp, ) + args
+        elif use_module:
             exe = "python"
             args = ("-m", "pip") + args
         else: