close filesystem on delete (#319)

* close filesystem on delete

* changelog

Author: willmcgugan

CHANGELOG.md

@@ -16,6 +16,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - `MemFS` now immediately releases all memory it holds when `close()` is called,
   rather than when it gets garbage collected. Closes [issue #308](https://github.com/PyFilesystem/pyfilesystem2/issues/308).
 - `FTPFS` now translates `EOFError` into `RemoteConnectionError`. Closes [#292](https://github.com/PyFilesystem/pyfilesystem2/issues/292)
+- Added automatic close for filesystems that go out of scope. Fixes [#298](https://github.com/PyFilesystem/pyfilesystem2/issues/298)
 
 ## [2.4.8] - 2019-06-12
 

fs/base.py

@@ -112,6 +112,10 @@ def __init__(self):
         self._lock = threading.RLock()
         super(FS, self).__init__()
 
+    def __del__(self):
+        """Auto-close the filesystem on exit."""
+        self.close()
+
     def __enter__(self):
         # type: (...) -> FS
         """Allow use of filesystem as a context manager.