bpo-30441: Fix bug when modifying os.environ while iterating over it #2409
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osantana
changed the title
Lib/os.py
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| @@ -697,7 +697,8 @@ def __delitem__(self, key): | |||
| raise KeyError(key) from None | |||
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| def __iter__(self): | |||
| for key in self._data: | |||
| data = list(self._data) | |||
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Either inline data or rename it to keys. Add an explaining comment about atomicity of list() from dict.
Lib/test/test_os.py
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| @@ -835,6 +835,21 @@ def test_key_type(self): | |||
| self.assertIs(cm.exception.args[0], missing) | |||
| self.assertTrue(cm.exception.__suppress_context__) | |||
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| def test_iter_error_when_os_environ_changes(self): | |||
| def _iter_environ_change(): | |||
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You can just use iter(os.environ.items()).
It may be worth to test also other iterators: iter(os.environ) and iter(os.environ.values()).
Lib/test/test_os.py
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| # add a new key in os.environ mapping | ||
| new_key = "__{}".format(key) | ||
| os.environ[new_key] = value |
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Don't forget to remove the added key.
No. Creating a tuple from a dict is not atomic now. |
Misc/ACKS
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| @@ -1760,3 +1760,4 @@ Jelle Zijlstra | |||
| Gennadiy Zlobin | |||
| Doug Zongker | |||
| Peter Åstrand | |||
| Osvaldo Santana Neto | |||
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Names are ordered in alphabetical order. You name presumably should be under the letter N.
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Are you sure? I didn't see an alphabetical order, so, I assumed I should put my name at the end of file...
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Oh! I see now!... It's alphabetical order of surname (not the first name)
Lib/test/test_os.py
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| next(iterator) # force iteration over modified mapping | ||
| self.assertEqual(os.environ[new_key], "test_environ_iteration") | ||
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| del os.environ[new_key] |
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The new key should be removed even if the test is failed, otherwise it could affect other tests. Use try...finally.
Lib/test/test_os.py
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| def test_iter_error_when_changing_os_environ_values(self): | ||
| iter_environ_values = iter(os.environ.values()) | ||
| self._test_environ_iteration(iter_environ_values) |
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Why repeat "iter environ values" so much times? Why not inline the iter_environ_values variable?
serhiy-storchaka
added
needs backport to 3.5
type-bug
…er it (pythonGH-2409). (cherry picked from commit 8a8d285)
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GH-2556 is a backport of this pull request to the 3.6 branch. |
…er it (pythonGH-2409). (cherry picked from commit 8a8d285)
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GH-2557 is a backport of this pull request to the 3.5 branch. |
Opening this pull request at Serhiy Storchaka's request to correct Bug #30441.
Question: Would not it be better to use tuple() instead of list() at
Lib/os.py:700?