1 files changed, 27 insertions, 0 deletions
diff --git a/Lib/test/test_support.py b/Lib/test/test_support.py
index 75563cb..b578bcd 100644
--- a/Lib/test/test_support.py
+++ b/Lib/test/test_support.py
@@ -669,6 +669,33 @@ TESTFN = "{}_{}_tmp".format(TESTFN, os.getpid())
 SAVEDCWD = os.getcwd()
 
 @contextlib.contextmanager
+def change_cwd(path, quiet=False):
+    """Return a context manager that changes the current working directory.
+
+    Arguments:
+
+      path: the directory to use as the temporary current working directory.
+
+      quiet: if False (the default), the context manager raises an exception
+        on error.  Otherwise, it issues only a warning and keeps the current
+        working directory the same.
+
+    """
+    saved_dir = os.getcwd()
+    try:
+        os.chdir(path)
+    except OSError:
+        if not quiet:
+            raise
+        warnings.warn('tests may fail, unable to change CWD to: ' + path,
+                      RuntimeWarning, stacklevel=3)
+    try:
+        yield os.getcwd()
+    finally:
+        os.chdir(saved_dir)
+
+
+@contextlib.contextmanager
 def temp_cwd(name='tempcwd', quiet=False):
     """
     Context manager that creates a temporary directory and set it as CWD.