refactor! EnvironmentVarGuard to tests/environment.py

Author: tony

src/libtmux/test/__init__.py

@@ -300,57 +300,3 @@ def temp_window(
         if len(session.windows.filter(window_id=window_id)) > 0:
             window.kill()
     return
-
-
-class EnvironmentVarGuard:
-    """Mock environmental variables safely.
-
-    Helps rotect the environment variable properly.  Can be used as context
-    manager.
-
-    Notes
-    -----
-    Vendorized to fix issue with Anaconda Python 2 not including test module,
-    see #121 [1]_
-
-    References
-    ----------
-    .. [1] Just installed, "ImportError: cannot import name test_support".
-       GitHub issue for tmuxp. https://github.com/tmux-python/tmuxp/issues/121.
-       Created October 12th, 2015. Accessed April 7th, 2018.
-    """
-
-    def __init__(self) -> None:
-        self._environ = os.environ
-        self._unset: set[str] = set()
-        self._reset: dict[str, str] = {}
-
-    def set(self, envvar: str, value: str) -> None:
-        """Set environment variable."""
-        if envvar not in self._environ:
-            self._unset.add(envvar)
-        else:
-            self._reset[envvar] = self._environ[envvar]
-        self._environ[envvar] = value
-
-    def unset(self, envvar: str) -> None:
-        """Unset environment variable."""
-        if envvar in self._environ:
-            self._reset[envvar] = self._environ[envvar]
-            del self._environ[envvar]
-
-    def __enter__(self) -> Self:
-        """Return context for for context manager."""
-        return self
-
-    def __exit__(
-        self,
-        exc_type: type[BaseException] | None,
-        exc_value: BaseException | None,
-        exc_tb: types.TracebackType | None,
-    ) -> None:
-        """Cleanup to run after context manager finishes."""
-        for envvar, value in self._reset.items():
-            self._environ[envvar] = value
-        for unset in self._unset:
-            del self._environ[unset]

src/libtmux/test/environment.py

@@ -0,0 +1,72 @@
+"""Helper methods for libtmux and downstream libtmux libraries."""
+
+from __future__ import annotations
+
+import logging
+import os
+import typing as t
+
+logger = logging.getLogger(__name__)
+
+if t.TYPE_CHECKING:
+    import sys
+    import types
+
+    if sys.version_info >= (3, 11):
+        from typing import Self
+    else:
+        from typing_extensions import Self
+
+
+class EnvironmentVarGuard:
+    """Mock environmental variables safely.
+
+    Helps rotect the environment variable properly.  Can be used as context
+    manager.
+
+    Notes
+    -----
+    Vendorized to fix issue with Anaconda Python 2 not including test module,
+    see #121 [1]_
+
+    References
+    ----------
+    .. [1] Just installed, "ImportError: cannot import name test_support".
+       GitHub issue for tmuxp. https://github.com/tmux-python/tmuxp/issues/121.
+       Created October 12th, 2015. Accessed April 7th, 2018.
+    """
+
+    def __init__(self) -> None:
+        self._environ = os.environ
+        self._unset: set[str] = set()
+        self._reset: dict[str, str] = {}
+
+    def set(self, envvar: str, value: str) -> None:
+        """Set environment variable."""
+        if envvar not in self._environ:
+            self._unset.add(envvar)
+        else:
+            self._reset[envvar] = self._environ[envvar]
+        self._environ[envvar] = value
+
+    def unset(self, envvar: str) -> None:
+        """Unset environment variable."""
+        if envvar in self._environ:
+            self._reset[envvar] = self._environ[envvar]
+            del self._environ[envvar]
+
+    def __enter__(self) -> Self:
+        """Return context for for context manager."""
+        return self
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_value: BaseException | None,
+        exc_tb: types.TracebackType | None,
+    ) -> None:
+        """Cleanup to run after context manager finishes."""
+        for envvar, value in self._reset.items():
+            self._environ[envvar] = value
+        for unset in self._unset:
+            del self._environ[unset]