(WIP): add tests

Author: akx

tests/tox_env/test_cachedir_tag.py

@@ -0,0 +1,24 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from tox.pytest import ToxProjectCreator
+
+
+def test_cachedir_tag_created_in_new_workdir(tox_project: ToxProjectCreator) -> None:
+    prj = tox_project({"tox.ini": "[testenv]\ncommands=python --version"})
+    cwd = prj.path
+    assert not (cwd / ".tox").exists()
+    result = prj.run("run", from_cwd=cwd)
+    result.assert_success()
+    assert (cwd / ".tox" / "CACHEDIR.TAG").exists()
+
+
+def test_cachedir_tag_not_created_in_extant_workdir(tox_project: ToxProjectCreator, tmp_path) -> None:
+    workdir = tmp_path / "workworkwork"
+    workdir.mkdir(parents=True)
+    prj = tox_project({"tox.ini": "[testenv]\ncommands=python --version"})
+    result = prj.run("--workdir", str(workdir), from_cwd=prj.path.parent)
+    result.assert_success()
+    assert not (workdir / "CACHEDIR.TAG").exists()