latest changes

test/vistir.py

@@ -0,0 +1,43 @@
+# Borrowed from Pew.
+# See https://github.com/berdario/pew/blob/master/pew/_utils.py#L82
+import os
+import sys
+from pathlib import Path
+
+from decorator import contextmanager
+
+
+@contextmanager
+def temp_environ():
+    """Allow the ability to set os.environ temporarily"""
+    environ = dict(os.environ)
+    try:
+        yield
+    finally:
+        os.environ.clear()
+        os.environ.update(environ)
+
+
+@contextmanager
+def temp_path():
+    """A context manager which allows the ability to set sys.path temporarily"""
+    path = [p for p in sys.path]
+    try:
+        yield
+    finally:
+        sys.path = [p for p in path]
+
+
+@contextmanager
+def cd(path):
+    """Context manager to temporarily change working directories"""
+    if not path:
+        return
+    prev_cwd = Path.cwd().as_posix()
+    if isinstance(path, Path):
+        path = path.as_posix()
+    os.chdir(str(path))
+    try:
+        yield
+    finally:
+        os.chdir(prev_cwd)