Add & use work_dir accessor

Author: akx

src/tox/tox_env/api.py

@@ -42,7 +42,7 @@ class ToxEnvCreateArgs(NamedTuple):
     log_handler: ToxHandler
 
 
-class ToxEnv(ABC):
+class ToxEnv(ABC):  # noqa: PLR0904
     """A tox environment."""
 
     def __init__(self, create_args: ToxEnvCreateArgs) -> None:
@@ -111,19 +111,19 @@ def register_config(self) -> None:
         self.conf.add_config(
             keys=["env_dir", "envdir"],
             of_type=Path,
-            default=lambda conf, name: cast(Path, conf.core["work_dir"]) / self.name,  # noqa: ARG005
+            default=lambda conf, name: self.work_dir / self.name,  # noqa: ARG005
             desc="directory assigned to the tox environment",
         )
         self.conf.add_config(
             keys=["env_tmp_dir", "envtmpdir"],
             of_type=Path,
-            default=lambda conf, name: cast(Path, conf.core["work_dir"]) / self.name / "tmp",  # noqa: ARG005
+            default=lambda conf, name: self.work_dir / self.name / "tmp",  # noqa: ARG005
             desc="a folder that is always reset at the start of the run",
         )
         self.conf.add_config(
             keys=["env_log_dir", "envlogdir"],
             of_type=Path,
-            default=lambda conf, name: cast(Path, conf.core["work_dir"]) / self.name / "log",  # noqa: ARG005
+            default=lambda conf, name: self.work_dir / self.name / "log",  # noqa: ARG005
             desc="a folder for logging where tox will put logs of tool invocation",
         )
         self.executor.register_conf(self)
@@ -194,6 +194,11 @@ def env_log_dir(self) -> Path:
         """:return: the tox environments log folder"""
         return cast(Path, self.conf["env_log_dir"])
 
+    @property
+    def work_dir(self) -> Path:
+        """:return: the tox work dir folder"""
+        return cast(Path, self.core["work_dir"])
+
     @property
     def name(self) -> str:
         return cast(str, self.conf["env_name"])
@@ -342,8 +347,8 @@ def environment_variables(self) -> dict[str, str]:
         for key in set_env:
             result[key] = set_env.load(key)
         result["TOX_ENV_NAME"] = self.name
-        result["TOX_WORK_DIR"] = str(self.core["work_dir"])
-        result["TOX_ENV_DIR"] = str(self.conf["env_dir"])
+        result["TOX_WORK_DIR"] = str(self.work_dir)
+        result["TOX_ENV_DIR"] = str(self.env_dir)
         return result
 
     @staticmethod