Load plugins from paths in 'pythonpath' option

Author: millerdev

changelog/11118.improvement.rst

@@ -0,0 +1,3 @@
+Allow plugins to be loaded with `-p` from paths specified in `pythonpath`.
+
+-- by :user:`millerdev`

doc/en/reference/reference.rst

@@ -1796,11 +1796,6 @@ passed multiple times. The expected format is ``name=value``. For example::
         [pytest]
         pythonpath = src1 src2
 
-   .. note::
-
-        ``pythonpath`` does not affect some imports that happen very early,
-        most notably plugins loaded using the ``-p`` command line option.
-
 
 .. confval:: required_plugins
 

src/_pytest/config/__init__.py

@@ -268,7 +268,6 @@ def directory_arg(path: str, optname: str) -> str:
     "warnings",
     "logging",
     "reports",
-    "python_path",
     "unraisableexception",
     "threadexception",
     "faulthandler",
@@ -1245,6 +1244,9 @@ def _initini(self, args: Sequence[str]) -> None:
         self._parser.extra_info["inifile"] = str(self.inipath)
         self._parser.addini("addopts", "Extra command line options", "args")
         self._parser.addini("minversion", "Minimally required pytest version")
+        self._parser.addini(
+            "pythonpath", type="paths", help="Add paths to sys.path", default=[]
+        )
         self._parser.addini(
             "required_plugins",
             "Plugins that must be present for pytest to run",
@@ -1294,6 +1296,18 @@ def _mark_plugins_for_rewrite(self, hook) -> None:
         for name in _iter_rewritable_modules(package_files):
             hook.mark_rewrite(name)
 
+    def _configure_python_path(self) -> None:
+        # `pythonpath = a b` will set `sys.path` to `[a, b, x, y, z, ...]`
+        for path in reversed(self.getini("pythonpath")):
+            sys.path.insert(0, str(path))
+        self.add_cleanup(self._unconfigure_python_path)
+
+    def _unconfigure_python_path(self) -> None:
+        for path in self.getini("pythonpath"):
+            path_str = str(path)
+            if path_str in sys.path:
+                sys.path.remove(path_str)
+
     def _validate_args(self, args: list[str], via: str) -> list[str]:
         """Validate known args."""
         self._parser._config_source_hint = via  # type: ignore
@@ -1370,6 +1384,7 @@ def _preparse(self, args: list[str], addopts: bool = True) -> None:
         )
         self._checkversion()
         self._consider_importhook(args)
+        self._configure_python_path()
         self.pluginmanager.consider_preparse(args, exclude_only=False)
         if not os.environ.get("PYTEST_DISABLE_PLUGIN_AUTOLOAD"):
             # Don't autoload from distribution package entry point. Only

src/_pytest/python_path.py

@@ -1409,7 +1409,6 @@ def pytest_load_initial_conftests(self):
         ("_pytest.config", "nonwrapper"),
         (m.__module__, "nonwrapper"),
         ("_pytest.legacypath", "nonwrapper"),
-        ("_pytest.python_path", "nonwrapper"),
         ("_pytest.capture", "wrapper"),
         ("_pytest.warnings", "wrapper"),
     ]

testing/test_config.py

@@ -3,7 +3,6 @@
 
 import sys
 from textwrap import dedent
-from typing import Generator
 
 from _pytest.pytester import Pytester
 import pytest
@@ -62,6 +61,26 @@ def test_two_dirs(pytester: Pytester, file_structure) -> None:
     result.assert_outcomes(passed=2)
 
 
+def test_local_plugin(pytester: Pytester, file_structure) -> None:
+    localplugin_py = pytester.path / "sub" / "localplugin.py"
+    content = dedent(
+        """
+        def pytest_load_initial_conftests():
+            print("local plugin load")
+
+        def pytest_unconfigure():
+            print("local plugin unconfig")
+        """
+    )
+    localplugin_py.write_text(content, encoding="utf-8")
+
+    pytester.makefile(".ini", pytest="[pytest]\npythonpath=sub\n")
+    result = pytester.runpytest("-plocalplugin", "-s", "test_foo.py")
+    result.stdout.fnmatch_lines(["local plugin load", "local plugin unconfig"])
+    assert result.ret == 0
+    result.assert_outcomes(passed=1)
+
+
 def test_module_not_found(pytester: Pytester, file_structure) -> None:
     """Without the pythonpath setting, the module should not be found."""
     pytester.makefile(".ini", pytest="[pytest]\n")
@@ -95,16 +114,13 @@ def test_clean_up(pytester: Pytester) -> None:
     after: list[str] | None = None
 
     class Plugin:
-        @pytest.hookimpl(wrapper=True, tryfirst=True)
-        def pytest_unconfigure(self) -> Generator[None, None, None]:
-            nonlocal before, after
+        @pytest.hookimpl(tryfirst=True)
+        def pytest_unconfigure(self) -> None:
+            nonlocal before
             before = sys.path.copy()
-            try:
-                return (yield)
-            finally:
-                after = sys.path.copy()
 
     result = pytester.runpytest_inprocess(plugins=[Plugin()])
+    after = sys.path.copy()
     assert result.ret == 0
 
     assert before is not None