explicitly detect conda envs - fixes #12652

initially we accidentially detected conda environmnts by just testing too many files
after steamlining we no longer detected conda environments
now we explicitly detect conda environments and test for support

Author: RonnyPfannschmidt

changelog/12652.bugfix.rst

@@ -0,0 +1,4 @@
+Resolve the regression in conda environment detection by
+explicitly expanding virtualenv detection to conda environents
+
+-- by :user:`RonnyPfannschmidt`

src/_pytest/main.py

@@ -370,9 +370,18 @@ def pytest_runtestloop(session: Session) -> bool:
 def _in_venv(path: Path) -> bool:
     """Attempt to detect if ``path`` is the root of a Virtual Environment by
     checking for the existence of the pyvenv.cfg file.
-    [https://peps.python.org/pep-0405/]"""
+
+    [https://peps.python.org/pep-0405/]
+
+    for regression protection we also check for conda environments that do not include pyenv.cfg yet
+    https://github.com/conda/conda/issues/13337 is the conda issue tracking adding pyenv.cfg
+
+    """
     try:
-        return path.joinpath("pyvenv.cfg").is_file()
+        return (
+            path.joinpath("pyvenv.cfg").is_file()
+            or path.joinpath("conda-meta", "history").is_file()
+        )
     except OSError:
         return False
 

testing/test_collection.py

@@ -3,6 +3,7 @@
 
 import os
 from pathlib import Path
+from pathlib import PurePath
 import pprint
 import shutil
 import sys
@@ -152,8 +153,17 @@ def test_ignored_certain_directories(self, pytester: Pytester) -> None:
         assert "test_notfound" not in s
         assert "test_found" in s
 
-    def test_ignored_virtualenvs(self, pytester: Pytester) -> None:
-        ensure_file(pytester.path / "virtual" / "pyvenv.cfg")
+    known_environment_types = pytest.mark.parametrize(
+        "env_path",
+        [
+            pytest.param(PurePath("pyvenv.cfg"), id="venv"),
+            pytest.param(PurePath("conda-meta", "history"), id="conda"),
+        ],
+    )
+
+    @known_environment_types
+    def test_ignored_virtualenvs(self, pytester: Pytester, env_path: PurePath) -> None:
+        ensure_file(pytester.path / "virtual" / env_path)
         testfile = ensure_file(pytester.path / "virtual" / "test_invenv.py")
         testfile.write_text("def test_hello(): pass", encoding="utf-8")
 
@@ -167,11 +177,12 @@ def test_ignored_virtualenvs(self, pytester: Pytester) -> None:
         result = pytester.runpytest("virtual")
         assert "test_invenv" in result.stdout.str()
 
+    @known_environment_types
     def test_ignored_virtualenvs_norecursedirs_precedence(
-        self, pytester: Pytester
+        self, pytester: Pytester, env_path
     ) -> None:
         # norecursedirs takes priority
-        ensure_file(pytester.path / ".virtual" / "pyvenv.cfg")
+        ensure_file(pytester.path / ".virtual" / env_path)
         testfile = ensure_file(pytester.path / ".virtual" / "test_invenv.py")
         testfile.write_text("def test_hello(): pass", encoding="utf-8")
         result = pytester.runpytest("--collect-in-virtualenv")
@@ -180,13 +191,14 @@ def test_ignored_virtualenvs_norecursedirs_precedence(
         result = pytester.runpytest("--collect-in-virtualenv", ".virtual")
         assert "test_invenv" in result.stdout.str()
 
-    def test__in_venv(self, pytester: Pytester) -> None:
+    @known_environment_types
+    def test__in_venv(self, pytester: Pytester, env_path: PurePath) -> None:
         """Directly test the virtual env detection function"""
-        # no pyvenv.cfg, not a virtualenv
+        # no env path, not a env
         base_path = pytester.mkdir("venv")
         assert _in_venv(base_path) is False
-        # with pyvenv.cfg, totally a virtualenv
-        base_path.joinpath("pyvenv.cfg").touch()
+        # with env path, totally a env
+        ensure_file(base_path.joinpath(env_path))
         assert _in_venv(base_path) is True
 
     def test_custom_norecursedirs(self, pytester: Pytester) -> None: