Berker Peksag added the comment:
The old tag() example has been replaced with a different example in
https://github.com/python/cpython/commit/bde782bb594edffeabe978abeee2b7082ab9bc2a
(bpo-33468)
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resolution: -> duplicate
stage: patch review -> resolved
status: open -> closed
super
cowlinator added the comment:
I would like to second the improved explanation of contextlib.contextmanager,
and additionally point out another problem:
A very important piece of information is missing from the documentation: how
to return data from the contextmanager-wrapped function.
I
Serhiy Storchaka added the comment:
swap_attr() looks too general. I think something more concrete would be better.
But the documentation already contain other examples for contextmanager.
closing() is good example, and redirect_stdout() would be good example.
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nosy: +serhiy.storchak
Berker Peksag added the comment:
We also have swap_attr() and swap_item() helpers in
Lib/test/support/__init__.py. I've used a simplified version of swap_attr() in
my patch.
Since this is basically a document improvement I removed Python 2.7 from the
versions field.
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keywords: +pat
Martin Panter added the comment:
You should probably use try / finally in your context manager to always restore
the attribute. Having said that, I recently wrote a similar context manager,
and then later discovered there is already “unittest.mock.patch” and/or
“unittest.mock.patch.object” via
New submission from Terry J. Reedy:
https://docs.python.org/3/library/contextlib.html#contextlib.contextmanager
The current html contextmanager example is 'not recommended' for actual use,
because there are better ways to accomplish the same goal. To me, is also
unsatifactory in that the conte
