MAINT: Close the file if any unexpected errors occur within memmap

1 files changed, 24 insertions, 1 deletions

diff --git a/numpy/compat/py3k.py b/numpy/compat/py3k.py
index d5bb2e4c7..ce4543bc3 100644
--- a/numpy/compat/py3k.py
+++ b/numpy/compat/py3k.py
@@ -7,7 +7,8 @@ from __future__ import division, absolute_import, print_function
 __all__ = ['bytes', 'asbytes', 'isfileobj', 'getexception', 'strchar',
            'unicode', 'asunicode', 'asbytes_nested', 'asunicode_nested',
            'asstr', 'open_latin1', 'long', 'basestring', 'sixu',
-           'integer_types', 'is_pathlib_path', 'npy_load_module', 'Path']
+           'integer_types', 'is_pathlib_path', 'npy_load_module', 'Path',
+           'contextlib_nullcontext']
 
 import sys
 try:
@@ -97,6 +98,28 @@ def is_pathlib_path(obj):
     """
     return Path is not None and isinstance(obj, Path)
 
+# from Python 3.7
+class contextlib_nullcontext(object):
+    """Context manager that does no additional processing.
+
+    Used as a stand-in for a normal context manager, when a particular
+    block of code is only sometimes used with a normal context manager:
+
+    cm = optional_cm if condition else nullcontext()
+    with cm:
+        # Perform operation, using optional_cm if condition is True
+    """
+
+    def __init__(self, enter_result=None):
+        self.enter_result = enter_result
+
+    def __enter__(self):
+        return self.enter_result
+
+    def __exit__(self, *excinfo):
+        pass
+
+
 if sys.version_info[0] >= 3 and sys.version_info[1] >= 4:
     def npy_load_module(name, fn, info=None):
         """