deprecating with contexts. closes #195

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## 1.10 -
 
+*   deprecated `_with` contexts [#195](https://github.com/amoffat/sh/issues/195)
 *   `_timeout_signal` allows you to specify your own signal to kill a timed-out process with.  use a constant from the `signal` stdlib module. [#171](https://github.com/amoffat/sh/issues/171)
 *   signal exceptions can now be caught by number or name.  `SignalException_9 == SignalException_SIGKILL`
 *   child processes that timeout via `_timeout` raise `sh.TimeoutException` instead of `sh.SignalExeception_9` [#172](https://github.com/amoffat/sh/issues/172)

sh.py

@@ -91,6 +91,15 @@ def callable(ob):
 import weakref
 
 
+# TODO remove with contexts in next version
+def with_context_warning():
+    warnings.warn("""
+with contexts are deprecated because they are not thread safe.  they will be \
+removed in the next version.  use subcommands instead \
+http://amoffat.github.io/sh/#sub-commands. see \
+https://github.com/amoffat/sh/issues/195
+""".strip(), stacklevel=3)
+
 
 
 if IS_PY3:
@@ -536,7 +545,7 @@ def __enter__(self):
         been done would have been done in the Command.__call__ call.
         essentially all that has to happen is the comand be pushed on the
         prepend stack. """
-        pass
+        with_context_warning()
 
     def __iter__(self):
         return self
@@ -930,6 +939,7 @@ def __unicode__(self):
         return self._path.decode(DEFAULT_ENCODING) + baked_args
 
     def __enter__(self):
+        with_context_warning()
         self(_with=True)
 
     def __exit__(self, typ, value, traceback):