bpo-31975 (PEP 565): Show DeprecationWarning in __main__ (GH-4458)
- primary change is to add a new default filter entry for 'default::DeprecationWarning:__main__' - secondary change is an internal one to cope with plain strings in the warning module's internal filter list (this avoids the need to create a compiled regex object early on during interpreter startup) - assorted documentation updates, including many more examples of configuring the warnings settings - additional tests to ensure that both the pure Python and the C accelerated warnings modules have the expected default configuration
This commit is contained in:
Nick Coghlan
GitHub
parent
d13889214a
commit
9b99747386
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@ -661,11 +661,13 @@ depending on the system error code.
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:pep:`3151` - Reworking the OS and IO exception hierarchy
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.. _warning-categories-as-exceptions:
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Warnings
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--------
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The following exceptions are used as warning categories; see the :mod:`warnings`
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module for more information.
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The following exceptions are used as warning categories; see the
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:ref:`warning-categories` documentation for more details.
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.. exception:: Warning
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@ -679,12 +681,14 @@ module for more information.
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.. exception:: DeprecationWarning
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Base class for warnings about deprecated features.
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Base class for warnings about deprecated features when those warnings are
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intended for other Python developers.
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.. exception:: PendingDeprecationWarning
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Base class for warnings about features which will be deprecated in the future.
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Base class for warnings about features which will be deprecated in the
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future.
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.. exception:: SyntaxWarning
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@ -699,8 +703,8 @@ module for more information.
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.. exception:: FutureWarning
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Base class for warnings about constructs that will change semantically in the
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future.
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Base class for warnings about deprecated features when those warnings are
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intended for end users of applications that are written in Python.
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.. exception:: ImportWarning
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@ -720,7 +724,8 @@ module for more information.
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.. exception:: ResourceWarning
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Base class for warnings related to resource usage.
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Base class for warnings related to resource usage. Ignored by the default
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warning filters.
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.. versionadded:: 3.2
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@ -51,8 +51,17 @@ Warning Categories
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------------------
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There are a number of built-in exceptions that represent warning categories.
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This categorization is useful to be able to filter out groups of warnings. The
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following warnings category classes are currently defined:
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This categorization is useful to be able to filter out groups of warnings.
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While these are technically
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:ref:`built-in exceptions <warning-categories-as-exceptions>`, they are
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documented here, because conceptually they belong to the warnings mechanism.
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User code can define additional warning categories by subclassing one of the
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standard warning categories. A warning category must always be a subclass of
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the :exc:`Warning` class.
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The following warnings category classes are currently defined:
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.. tabularcolumns:: |l|p{0.6\linewidth}|
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@ -66,7 +75,9 @@ following warnings category classes are currently defined:
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| :exc:`UserWarning` | The default category for :func:`warn`. |
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+----------------------------------+-----------------------------------------------+
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| :exc:`DeprecationWarning` | Base category for warnings about deprecated |
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| | features (ignored by default). |
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| | features when those warnings are intended for |
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| | other Python developers (ignored by default, |
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| | unless triggered by code in ``__main__``). |
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+----------------------------------+-----------------------------------------------+
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| :exc:`SyntaxWarning` | Base category for warnings about dubious |
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| | syntactic features. |
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@ -74,8 +85,10 @@ following warnings category classes are currently defined:
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| :exc:`RuntimeWarning` | Base category for warnings about dubious |
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| | runtime features. |
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+----------------------------------+-----------------------------------------------+
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| :exc:`FutureWarning` | Base category for warnings about constructs |
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| | that will change semantically in the future. |
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| :exc:`FutureWarning` | Base category for warnings about deprecated |
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| | features when those warnings are intended for |
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| | end users of applications that are written in |
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| | Python. |
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+----------------------------------+-----------------------------------------------+
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| :exc:`PendingDeprecationWarning` | Base category for warnings about features |
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| | that will be deprecated in the future |
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@ -95,13 +108,12 @@ following warnings category classes are currently defined:
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| | resource usage. |
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+----------------------------------+-----------------------------------------------+
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While these are technically built-in exceptions, they are documented here,
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because conceptually they belong to the warnings mechanism.
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User code can define additional warning categories by subclassing one of the
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standard warning categories. A warning category must always be a subclass of
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the :exc:`Warning` class.
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.. versionchanged:: 3.7
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Previously :exc:`DeprecationWarning` and :exc:`FutureWarning` were
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distinguished based on whether a feature was being removed entirely or
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changing its behaviour. They are now distinguished based on their
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intended audience and the way they're handled by the default warnings
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filters.
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.. _warning-filter:
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@ -114,7 +126,7 @@ into errors (raising an exception).
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Conceptually, the warnings filter maintains an ordered list of filter
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specifications; any specific warning is matched against each filter
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specification in the list in turn until a match is found; the match determines
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specification in the list in turn until a match is found; the filter determines
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the disposition of the match. Each entry is a tuple of the form (*action*,
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*message*, *category*, *module*, *lineno*), where:
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@ -123,19 +135,19 @@ the disposition of the match. Each entry is a tuple of the form (*action*,
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+---------------+----------------------------------------------+
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| Value | Disposition |
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+===============+==============================================+
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| ``"default"`` | print the first occurrence of matching |
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| | warnings for each location (module + |
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| | line number) where the warning is issued |
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+---------------+----------------------------------------------+
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| ``"error"`` | turn matching warnings into exceptions |
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+---------------+----------------------------------------------+
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| ``"ignore"`` | never print matching warnings |
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+---------------+----------------------------------------------+
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| ``"always"`` | always print matching warnings |
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+---------------+----------------------------------------------+
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| ``"default"`` | print the first occurrence of matching |
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| | warnings for each location where the warning |
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| | is issued |
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+---------------+----------------------------------------------+
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| ``"module"`` | print the first occurrence of matching |
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| | warnings for each module where the warning |
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| | is issued |
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| | is issued (regardless of line number) |
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+---------------+----------------------------------------------+
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| ``"once"`` | print only the first occurrence of matching |
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| | warnings, regardless of location |
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@ -157,33 +169,119 @@ the disposition of the match. Each entry is a tuple of the form (*action*,
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Since the :exc:`Warning` class is derived from the built-in :exc:`Exception`
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class, to turn a warning into an error we simply raise ``category(message)``.
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If a warning is reported and doesn't match any registered filter then the
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"default" action is applied (hence its name).
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.. _describing-warning-filters:
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Describing Warning Filters
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~~~~~~~~~~~~~~~~~~~~~~~~~~
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The warnings filter is initialized by :option:`-W` options passed to the Python
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interpreter command line. The interpreter saves the arguments for all
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:option:`-W` options without interpretation in ``sys.warnoptions``; the
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:mod:`warnings` module parses these when it is first imported (invalid options
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are ignored, after printing a message to ``sys.stderr``).
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interpreter command line and the :envvar:`PYTHONWARNINGS` environment variable.
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The interpreter saves the arguments for all supplied entries without
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interpretation in ``sys.warnoptions``; the :mod:`warnings` module parses these
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when it is first imported (invalid options are ignored, after printing a
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message to ``sys.stderr``).
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Individual warnings filters are specified as a sequence of fields separated by
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colons::
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action:message:category:module:line
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The meaning of each of these fields is as described in :ref:`warning-filter`.
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When listing multiple filters on a single line (as for
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:envvar:`PYTHONWARNINGS`), the individual filters are separated by commas,and
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the filters listed later take precedence over those listed before them (as
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they're applied left-to-right, and the most recently applied filters take
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precedence over earlier ones).
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Commonly used warning filters apply to either all warnings, warnings in a
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particular category, or warnings raised by particular modules or packages.
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Some examples::
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default # Show all warnings (even those ignored by default)
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ignore # Ignore all warnings
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error # Convert all warnings to errors
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error::ResourceWarning # Treat ResourceWarning messages as errors
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default::DeprecationWarning # Show DeprecationWarning messages
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ignore,default:::mymodule # Only report warnings triggered by "mymodule"
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error:::mymodule[.*] # Convert warnings to errors in "mymodule"
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# and any subpackages of "mymodule"
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Default Warning Filters
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~~~~~~~~~~~~~~~~~~~~~~~
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.. _default-warning-filter:
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Default Warning Filter
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~~~~~~~~~~~~~~~~~~~~~~
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By default, Python installs several warning filters, which can be overridden by
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the command-line options passed to :option:`-W` and calls to
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:func:`filterwarnings`.
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the :option:`-W` command-line option, the :envvar:`PYTHONWARNINGS` environment
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variable and calls to :func:`filterwarnings`.
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* :exc:`DeprecationWarning` and :exc:`PendingDeprecationWarning`, and
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:exc:`ImportWarning` are ignored.
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In regular release builds, the default warning filter has the following entries
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(in order of precedence)::
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* :exc:`BytesWarning` is ignored unless the :option:`-b` option is given once or
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twice; in this case this warning is either printed (``-b``) or turned into an
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exception (``-bb``).
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default::DeprecationWarning:__main__
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ignore::DeprecationWarning
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ignore::PendingDeprecationWarning
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ignore::ImportWarning
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ignore::ResourceWarning
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* :exc:`ResourceWarning` is ignored unless Python was built in debug mode.
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In debug builds, the list of default warning filters is empty.
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.. versionchanged:: 3.2
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:exc:`DeprecationWarning` is now ignored by default in addition to
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:exc:`PendingDeprecationWarning`.
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.. versionchanged:: 3.7
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:exc:`DeprecationWarning` is once again shown by default when triggered
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directly by code in ``__main__``.
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.. versionchanged:: 3.7
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:exc:`BytesWarning` no longer appears in the default filter list and is
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instead configured via :data:`sys.warnoptions` when :option:`-b` is specified
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twice.
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.. _warning-disable:
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Overriding the default filter
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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Developers of applications written in Python may wish to hide *all* Python level
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warnings from their users by default, and only display them when running tests
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or otherwise working on the application. The :data:`sys.warnoptions` attribute
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used to pass filter configurations to the interpreter can be used as a marker to
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indicate whether or not warnings should be disabled::
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import sys
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if not sys.warnoptions:
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import warnings
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warnings.simplefilter("ignore")
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Developers of test runners for Python code are advised to instead ensure that
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*all* warnings are displayed by default for the code under test, using code
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like::
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import sys
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if not sys.warnoptions:
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import os, warnings
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warnings.simplefilter("default") # Change the filter in this process
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os.environ["PYTHONWARNINGS"] = "default" # Also affect subprocesses
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Finally, developers of interactive shells that run user code in a namespace
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other than ``__main__`` are advised to ensure that :exc:`DeprecationWarning`
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messages are made visible by default, using code like the following (where
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``user_ns`` is the module used to execute code entered interactively)::
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import warnings
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warnings.filterwarnings("default", category=DeprecationWarning,
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module=user_ns.get("__name__"))
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.. _warning-suppress:
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@ -191,7 +289,8 @@ Temporarily Suppressing Warnings
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--------------------------------
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If you are using code that you know will raise a warning, such as a deprecated
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function, but do not want to see the warning, then it is possible to suppress
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function, but do not want to see the warning (even when warnings have been
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explicitly configured via the command line), then it is possible to suppress
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the warning using the :class:`catch_warnings` context manager::
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import warnings
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@ -261,38 +360,30 @@ entries from the warnings list before each new operation).
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.. _warning-ignored:
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Updating Code For New Versions of Python
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----------------------------------------
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Updating Code For New Versions of Dependencies
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----------------------------------------------
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Warnings that are only of interest to the developer are ignored by default. As
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such you should make sure to test your code with typically ignored warnings
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made visible. You can do this from the command-line by passing :option:`-Wd <-W>`
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to the interpreter (this is shorthand for :option:`!-W default`). This enables
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default handling for all warnings, including those that are ignored by default.
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To change what action is taken for encountered warnings you simply change what
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argument is passed to :option:`-W`, e.g. :option:`!-W error`. See the
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:option:`-W` flag for more details on what is possible.
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Warning categories that are primarily of interest to Python developers (rather
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than end users of applications written in Python) are ignored by default.
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To programmatically do the same as :option:`!-Wd`, use::
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Notably, this "ignored by default" list includes :exc:`DeprecationWarning`
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(for every module except ``__main__``), which means developers should make sure
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to test their code with typically ignored warnings made visible in order to
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receive timely notifications of future breaking API changes (whether in the
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standard library or third party packages).
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warnings.simplefilter('default')
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In the ideal case, the code will have a suitable test suite, and the test runner
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will take care of implicitly enabling all warnings when running tests
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(the test runner provided by the :mod:`unittest` module does this).
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Make sure to execute this code as soon as possible. This prevents the
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registering of what warnings have been raised from unexpectedly influencing how
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future warnings are treated.
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Having certain warnings ignored by default is done to prevent a user from
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seeing warnings that are only of interest to the developer. As you do not
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necessarily have control over what interpreter a user uses to run their code,
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it is possible that a new version of Python will be released between your
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release cycles. The new interpreter release could trigger new warnings in your
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code that were not there in an older interpreter, e.g.
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:exc:`DeprecationWarning` for a module that you are using. While you as a
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developer want to be notified that your code is using a deprecated module, to a
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user this information is essentially noise and provides no benefit to them.
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The :mod:`unittest` module has been also updated to use the ``'default'``
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filter while running tests.
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In less ideal cases, applications can be checked for use of deprecated
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interfaces by passing :option:`-Wd <-W>` to the Python interpreter (this is
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shorthand for :option:`!-W default`) or setting ``PYTHONWARNINGS=default`` in
|
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the environment. This enables default handling for all warnings, including those
|
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that are ignored by default. To change what action is taken for encountered
|
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warnings you can change what argument is passed to :option:`-W` (e.g.
|
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:option:`!-W error`). See the :option:`-W` flag for more details on what is
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possible.
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.. _warning-functions:
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|
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@ -259,12 +259,8 @@ tutorial/stdlib2,,:start,extra = data[start:start+extra_size]
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tutorial/stdlib2,,:start,"fields = struct.unpack('<IIIHH', data[start:start+16])"
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tutorial/stdlib2,,:start,filename = data[start:start+filenamesize]
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tutorial/stdlib2,,:Warning,WARNING:root:Warning:config file server.conf not found
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using/cmdline,,:category,action:message:category:module:line
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using/cmdline,,:errorhandler,:errorhandler
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using/cmdline,,:line,action:message:category:module:line
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using/cmdline,,:line,file:line: category: message
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using/cmdline,,:message,action:message:category:module:line
|
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using/cmdline,,:module,action:message:category:module:line
|
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using/unix,,:Packaging,https://en.opensuse.org/Portal:Packaging
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whatsnew/2.0,,:len,
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whatsnew/2.3,,::,
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@ -302,6 +298,20 @@ whatsnew/3.2,,:prefix,zope-conf = ${custom:prefix}/etc/zope.conf
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library/re,,`,!#$%&'*+-.^_`|~:
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library/re,,`,!\#\$%\&'\*\+\-\.\^_`\|\~:
|
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library/tarfile,,:xz,'x:xz'
|
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library/warnings,,:message,action:message:category:module:line
|
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library/warnings,,:category,action:message:category:module:line
|
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library/warnings,,:module,action:message:category:module:line
|
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library/warnings,,:line,action:message:category:module:line
|
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library/warnings,,::,error::ResourceWarning
|
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library/warnings,,::,default::DeprecationWarning
|
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library/warnings,,::,default:::mymodule
|
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library/warnings,,:mymodule,default:::mymodule
|
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library/warnings,,::,error:::mymodule
|
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library/warnings,,:mymodule,error:::mymodule
|
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library/warnings,,::,ignore::DeprecationWarning
|
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library/warnings,,::,ignore::PendingDeprecationWarning
|
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library/warnings,,::,ignore::ImportWarning
|
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library/warnings,,::,ignore::ResourceWarning
|
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library/xml.etree.elementtree,,:sometag,prefix:sometag
|
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library/xml.etree.elementtree,,:fictional,"<actors xmlns:fictional=""http://characters.example.com"""
|
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library/xml.etree.elementtree,,:character,<fictional:character>Lancelot</fictional:character>
|
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|
|
@ -330,3 +340,4 @@ whatsnew/3.7,,`,'`'
|
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whatsnew/3.7,,::,error::BytesWarning
|
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whatsnew/changelog,,::,error::BytesWarning
|
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whatsnew/changelog,,::,default::BytesWarning
|
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whatsnew/changelog,,::,default::DeprecationWarning
|
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|
|
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|
|
|
@ -356,49 +356,27 @@ Miscellaneous options
|
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:option:`-W` options are ignored (though, a warning message is printed about
|
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invalid options when the first warning is issued).
|
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|
||||
Warnings can also be controlled from within a Python program using the
|
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Warnings can also be controlled using the :envvar:`PYTHONWARNINGS`
|
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environment variable and from within a Python program using the
|
||||
:mod:`warnings` module.
|
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|
||||
The simplest form of argument is one of the following action strings (or a
|
||||
unique abbreviation):
|
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The simplest settings apply a particular action unconditionally to all
|
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warnings emitted by a process (even those that are otherwise ignored by
|
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default)::
|
||||
|
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``ignore``
|
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Ignore all warnings.
|
||||
``default``
|
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Explicitly request the default behavior (printing each warning once per
|
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source line).
|
||||
``all``
|
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Print a warning each time it occurs (this may generate many messages if a
|
||||
warning is triggered repeatedly for the same source line, such as inside a
|
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loop).
|
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``module``
|
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Print each warning only the first time it occurs in each module.
|
||||
``once``
|
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Print each warning only the first time it occurs in the program.
|
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``error``
|
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Raise an exception instead of printing a warning message.
|
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-Wdefault # Warn once per call location
|
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-Werror # Convert to exceptions
|
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-Walways # Warn every time
|
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-Wmodule # Warn once per calling module
|
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-Wonce # Warn once per Python process
|
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-Wignore # Never warn
|
||||
|
||||
The full form of argument is::
|
||||
The action names can be abbreviated as desired (e.g. ``-Wi``, ``-Wd``,
|
||||
``-Wa``, ``-We``) and the interpreter will resolve them to the appropriate
|
||||
action name.
|
||||
|
||||
action:message:category:module:line
|
||||
|
||||
Here, *action* is as explained above but only applies to messages that match
|
||||
the remaining fields. Empty fields match all values; trailing empty fields
|
||||
may be omitted. The *message* field matches the start of the warning message
|
||||
printed; this match is case-insensitive. The *category* field matches the
|
||||
warning category. This must be a class name; the match tests whether the
|
||||
actual warning category of the message is a subclass of the specified warning
|
||||
category. The full class name must be given. The *module* field matches the
|
||||
(fully-qualified) module name; this match is case-sensitive. The *line*
|
||||
field matches the line number, where zero matches all line numbers and is
|
||||
thus equivalent to an omitted line number.
|
||||
|
||||
.. seealso::
|
||||
:mod:`warnings` -- the warnings module
|
||||
|
||||
:pep:`230` -- Warning framework
|
||||
|
||||
:envvar:`PYTHONWARNINGS`
|
||||
See :ref:`warning-filter` and :ref:`describing-warning-filters` for more
|
||||
details.
|
||||
|
||||
|
||||
.. cmdoption:: -x
|
||||
|
|
@ -659,7 +637,23 @@ conflict.
|
|||
|
||||
This is equivalent to the :option:`-W` option. If set to a comma
|
||||
separated string, it is equivalent to specifying :option:`-W` multiple
|
||||
times.
|
||||
times, with filters later in the list taking precedence over those earlier
|
||||
in the list.
|
||||
|
||||
The simplest settings apply a particular action unconditionally to all
|
||||
warnings emitted by a process (even those that are otherwise ignored by
|
||||
default)::
|
||||
|
||||
PYTHONWARNINGS=default # Warn once per call location
|
||||
PYTHONWARNINGS=error # Convert to exceptions
|
||||
PYTHONWARNINGS=always # Warn every time
|
||||
PYTHONWARNINGS=module # Warn once per calling module
|
||||
PYTHONWARNINGS=once # Warn once per Python process
|
||||
PYTHONWARNINGS=ignore # Never warn
|
||||
|
||||
See :ref:`warning-filter` and :ref:`describing-warning-filters` for more
|
||||
details.
|
||||
|
||||
|
||||
.. envvar:: PYTHONFAULTHANDLER
|
||||
|
||||
|
|
|
|||
|
|
@ -70,6 +70,7 @@ Summary -- Release highlights
|
|||
New Features
|
||||
============
|
||||
|
||||
|
||||
.. _whatsnew37-pep538:
|
||||
|
||||
PEP 538: Legacy C Locale Coercion
|
||||
|
|
@ -107,6 +108,7 @@ locale remains active when the core interpreter is initialized.
|
|||
:pep:`538` -- Coercing the legacy C locale to a UTF-8 based locale
|
||||
PEP written and implemented by Nick Coghlan.
|
||||
|
||||
|
||||
.. _whatsnew37-pep553:
|
||||
|
||||
PEP 553: Built-in breakpoint()
|
||||
|
|
@ -203,6 +205,44 @@ resolution on Linux and Windows.
|
|||
PEP written and implemented by Victor Stinner
|
||||
|
||||
|
||||
.. _whatsnew37-pep565:
|
||||
|
||||
PEP 565: Show DeprecationWarning in ``__main__``
|
||||
------------------------------------------------
|
||||
|
||||
The default handling of :exc:`DeprecationWarning` has been changed such that
|
||||
these warnings are once more shown by default, but only when the code
|
||||
triggering them is running directly in the ``__main__`` module. As a result,
|
||||
developers of single file scripts and those using Python interactively should
|
||||
once again start seeing deprecation warnings for the APIs they use, but
|
||||
deprecation warnings triggered by imported application, library and framework
|
||||
modules will continue to be hidden by default.
|
||||
|
||||
As a result of this change, the standard library now allows developers to choose
|
||||
between three different deprecation warning behaviours:
|
||||
|
||||
* :exc:`FutureWarning`: always displayed by default, recommended for warnings
|
||||
intended to be seen by application end users (e.g. for deprecated application
|
||||
configuration settings).
|
||||
* :exc:`DeprecationWarning`: displayed by default only in ``__main__`` and when
|
||||
running tests, recommended for warnings intended to be seen by other Python
|
||||
developers where a version upgrade may result in changed behaviour or an
|
||||
error.
|
||||
* :exc:`PendingDeprecationWarning`: displayed by default only when running
|
||||
tests, intended for cases where a future version upgrade will change the
|
||||
warning category to :exc:`DeprecationWarning` or :exc:`FutureWarning`.
|
||||
|
||||
Previously both :exc:`DeprecationWarning` and :exc:`PendingDeprecationWarning`
|
||||
were only visible when running tests, which meant that developers primarily
|
||||
writing single file scripts or using Python interactively could be surprised
|
||||
by breaking changes in the APIs they used.
|
||||
|
||||
.. seealso::
|
||||
|
||||
:pep:`565` -- Show DeprecationWarning in ``__main__``
|
||||
PEP written and implemented by Nick Coghlan
|
||||
|
||||
|
||||
PEP 540: Add a new UTF-8 mode
|
||||
-----------------------------
|
||||
|
||||
|
|
|
|||
|
|
@ -558,6 +558,7 @@ class CmdLineTest(unittest.TestCase):
|
|||
expected_filters = "default::Warning"
|
||||
else:
|
||||
expected_filters = ("default::Warning "
|
||||
"default::DeprecationWarning "
|
||||
"ignore::DeprecationWarning "
|
||||
"ignore::PendingDeprecationWarning "
|
||||
"ignore::ImportWarning "
|
||||
|
|
@ -626,6 +627,7 @@ class CmdLineTest(unittest.TestCase):
|
|||
"always::UserWarning")
|
||||
if not Py_DEBUG:
|
||||
expected_filters += (" "
|
||||
"default::DeprecationWarning "
|
||||
"ignore::DeprecationWarning "
|
||||
"ignore::PendingDeprecationWarning "
|
||||
"ignore::ImportWarning "
|
||||
|
|
|
|||
|
|
@ -16,6 +16,8 @@ import warnings as original_warnings
|
|||
py_warnings = support.import_fresh_module('warnings', blocked=['_warnings'])
|
||||
c_warnings = support.import_fresh_module('warnings', fresh=['_warnings'])
|
||||
|
||||
Py_DEBUG = hasattr(sys, 'gettotalrefcount')
|
||||
|
||||
@contextmanager
|
||||
def warnings_state(module):
|
||||
"""Use a specific warnings implementation in warning_tests."""
|
||||
|
|
@ -320,6 +322,7 @@ class FilterTests(BaseTest):
|
|||
self.module.filters[0][0], "error",
|
||||
"simplefilter did not promote filter to the beginning of list"
|
||||
)
|
||||
|
||||
def test_append_duplicate(self):
|
||||
with original_warnings.catch_warnings(module=self.module,
|
||||
record=True) as w:
|
||||
|
|
@ -1143,6 +1146,37 @@ class EnvironmentVariableTests(BaseTest):
|
|||
b" File \"<string>\", line 1, in <module>",
|
||||
b"DeprecationWarning: Message"])
|
||||
|
||||
def test_default_filter_configuration(self):
|
||||
pure_python_api = self.module is py_warnings
|
||||
if Py_DEBUG:
|
||||
expected_default_filters = []
|
||||
else:
|
||||
if pure_python_api:
|
||||
main_module_filter = re.compile("__main__")
|
||||
else:
|
||||
main_module_filter = "__main__"
|
||||
expected_default_filters = [
|
||||
('default', None, DeprecationWarning, main_module_filter, 0),
|
||||
('ignore', None, DeprecationWarning, None, 0),
|
||||
('ignore', None, PendingDeprecationWarning, None, 0),
|
||||
('ignore', None, ImportWarning, None, 0),
|
||||
('ignore', None, ResourceWarning, None, 0),
|
||||
]
|
||||
expected_output = [str(f).encode() for f in expected_default_filters]
|
||||
|
||||
if pure_python_api:
|
||||
# Disable the warnings acceleration module in the subprocess
|
||||
code = "import sys; sys.modules.pop('warnings', None); sys.modules['_warnings'] = None; "
|
||||
else:
|
||||
code = ""
|
||||
code += "import warnings; [print(f) for f in warnings.filters]"
|
||||
|
||||
rc, stdout, stderr = assert_python_ok("-c", code, __isolated=True)
|
||||
stdout_lines = [line.strip() for line in stdout.splitlines()]
|
||||
self.maxDiff = None
|
||||
self.assertEqual(stdout_lines, expected_output)
|
||||
|
||||
|
||||
@unittest.skipUnless(sys.getfilesystemencoding() != 'ascii',
|
||||
'requires non-ascii filesystemencoding')
|
||||
def test_nonascii(self):
|
||||
|
|
@ -1192,7 +1226,7 @@ a=A()
|
|||
rc, out, err = assert_python_ok("-c", code)
|
||||
# note: "__main__" filename is not correct, it should be the name
|
||||
# of the script
|
||||
self.assertEqual(err, b'__main__:7: UserWarning: test')
|
||||
self.assertEqual(err.decode(), '__main__:7: UserWarning: test')
|
||||
|
||||
def test_late_resource_warning(self):
|
||||
# Issue #21925: Emitting a ResourceWarning late during the Python
|
||||
|
|
|
|||
|
|
@ -519,8 +519,10 @@ except ImportError:
|
|||
# Module initialization
|
||||
_processoptions(sys.warnoptions)
|
||||
if not _warnings_defaults:
|
||||
# Several warning categories are ignored by default in Py_DEBUG builds
|
||||
# Several warning categories are ignored by default in regular builds
|
||||
if not hasattr(sys, 'gettotalrefcount'):
|
||||
filterwarnings("default", category=DeprecationWarning,
|
||||
module="__main__", append=1)
|
||||
simplefilter("ignore", category=DeprecationWarning, append=1)
|
||||
simplefilter("ignore", category=PendingDeprecationWarning, append=1)
|
||||
simplefilter("ignore", category=ImportWarning, append=1)
|
||||
|
|
|
|||
|
|
@ -0,0 +1,4 @@
|
|||
The default warning filter list now starts with a
|
||||
"default::DeprecationWarning:__main__" entry, so deprecation warnings are
|
||||
once again shown by default in single-file scripts and at the interactive
|
||||
prompt.
|
||||
|
|
@ -12,6 +12,7 @@ MODULE_NAME " provides basic warning filtering support.\n"
|
|||
_Py_IDENTIFIER(argv);
|
||||
_Py_IDENTIFIER(stderr);
|
||||
#ifndef Py_DEBUG
|
||||
_Py_IDENTIFIER(default);
|
||||
_Py_IDENTIFIER(ignore);
|
||||
#endif
|
||||
|
||||
|
|
@ -22,8 +23,20 @@ check_matched(PyObject *obj, PyObject *arg)
|
|||
_Py_IDENTIFIER(match);
|
||||
int rc;
|
||||
|
||||
/* A 'None' filter always matches */
|
||||
if (obj == Py_None)
|
||||
return 1;
|
||||
|
||||
/* An internal plain text default filter must match exactly */
|
||||
if (PyUnicode_CheckExact(obj)) {
|
||||
int cmp_result = PyUnicode_Compare(obj, arg);
|
||||
if (cmp_result == -1 && PyErr_Occurred()) {
|
||||
return -1;
|
||||
}
|
||||
return !cmp_result;
|
||||
}
|
||||
|
||||
/* Otherwise assume a regex filter and call its match() method */
|
||||
result = _PyObject_CallMethodIdObjArgs(obj, &PyId_match, arg, NULL);
|
||||
if (result == NULL)
|
||||
return -1;
|
||||
|
|
@ -1158,16 +1171,27 @@ static PyMethodDef warnings_functions[] = {
|
|||
|
||||
#ifndef Py_DEBUG
|
||||
static PyObject *
|
||||
create_filter(PyObject *category, _Py_Identifier *id)
|
||||
create_filter(PyObject *category, _Py_Identifier *id, const char *modname)
|
||||
{
|
||||
PyObject *modname_obj = NULL;
|
||||
PyObject *action_str = _PyUnicode_FromId(id);
|
||||
if (action_str == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Default to "no module name" for initial filter set */
|
||||
if (modname != NULL) {
|
||||
modname_obj = PyUnicode_InternFromString(modname);
|
||||
if (modname_obj == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
} else {
|
||||
modname_obj = Py_None;
|
||||
}
|
||||
|
||||
/* This assumes the line number is zero for now. */
|
||||
return PyTuple_Pack(5, action_str, Py_None,
|
||||
category, Py_None, _PyLong_Zero);
|
||||
category, modname_obj, _PyLong_Zero);
|
||||
}
|
||||
#endif
|
||||
|
||||
|
|
@ -1180,20 +1204,22 @@ init_filters(void)
|
|||
return PyList_New(0);
|
||||
#else
|
||||
/* Other builds ignore a number of warning categories by default */
|
||||
PyObject *filters = PyList_New(4);
|
||||
PyObject *filters = PyList_New(5);
|
||||
if (filters == NULL) {
|
||||
return NULL;
|
||||
}
|
||||
|
||||
size_t pos = 0; /* Post-incremented in each use. */
|
||||
PyList_SET_ITEM(filters, pos++,
|
||||
create_filter(PyExc_DeprecationWarning, &PyId_ignore));
|
||||
create_filter(PyExc_DeprecationWarning, &PyId_default, "__main__"));
|
||||
PyList_SET_ITEM(filters, pos++,
|
||||
create_filter(PyExc_PendingDeprecationWarning, &PyId_ignore));
|
||||
create_filter(PyExc_DeprecationWarning, &PyId_ignore, NULL));
|
||||
PyList_SET_ITEM(filters, pos++,
|
||||
create_filter(PyExc_ImportWarning, &PyId_ignore));
|
||||
create_filter(PyExc_PendingDeprecationWarning, &PyId_ignore, NULL));
|
||||
PyList_SET_ITEM(filters, pos++,
|
||||
create_filter(PyExc_ResourceWarning, &PyId_ignore));
|
||||
create_filter(PyExc_ImportWarning, &PyId_ignore, NULL));
|
||||
PyList_SET_ITEM(filters, pos++,
|
||||
create_filter(PyExc_ResourceWarning, &PyId_ignore, NULL));
|
||||
|
||||
for (size_t x = 0; x < pos; x++) {
|
||||
if (PyList_GET_ITEM(filters, x) == NULL) {
|
||||
|
|
|
|||
Loading…
Reference in New Issue